Forensic Medicine Notes 157 Pages-1.pdf

FORENSIC MEDICINE
1. Legal Medicine
2. Medical Law and Ethics
3. Death and Medicolegal Importance
4. Autopsy
5. Post Mortem Changes
6. Mechanical Injury
7. Ballistics
8. Thermal Burns
9. Asphyxia
10.Drowning
11.Forensic Psychiatry
12.Impotence and Sterility
13.Infanticide
14.Sexual Jurisprudence
15.Agricultural Poisons
16.Corrosives
17.Deliriants
18.Somniferous Agents
19.Psychotropics and Hallucinogens
20.Spinal Poisons
21.Respiratory Poisons
22.Inebriants
23.Inorganic Non-Metallic Irritant
24.Heavy Metal Irritants
25.Organic Irritants

1. LEGAL MEDICINE
DEFINITIONS:
Forensic Medicine
It deals with application of medical knowledge to law to aid the
administration of justice.
Medicine Law Justice
Medical Jurisprudence:
It is the study of legal rules and regulations that guides the medical profession
in their dealings with their patients, with each other and with the state.
Law Medical profession
Patients Other Doctors State
Medical Ethics:
It is the study of Moral principles that guides the medical profession in their
dealings with their patients, with each other and with the state.
Moral principles Medical profession
Patients Other Doctors State
Medical Etiquette:
It deals with conventional laws of courtesy observed between members of
Medical Profession.
Courtesy behavior
Doctor Doctor
INDIAN LEGAL SYSTEM
Indian penal code 1860: IPC
Defines various crimes and punishment admissible under court of law.
Criminal procedure code 1973: Crpc
Defines the procedure of investigations and trial of offences in whole
of India.
Indian evidence act 1872: IEA
Relates to evidences upon which courts come to conclusion in each
case.
INQUEST:
An enquiry into the cause of death in all cases of Sudden, Suspicious
&Unnatural deaths
Types of Inquest:
1. Police inquest
2. Magistrate inquest
3. Coroner’s inquest
4. Medical examiners system
POLICE INQUEST:
 Investigating police officer not below rank of sub inspector
 Receipt of information about suspicious death
 Informs Concerned Magistrate
 Proceeds To Crime Area And Prepares A Report
 With witness of two respectable person –“Panchas”
SUDDEN DEATH:
 If suspicious sent for postmortem

 If not suspicious hand over the body to relatives
PANCHANAMA
 Apparent cause of death
 Injuries
 Manner of death
 Signed by witness –“Panchas”
MAGISTRATE INQUEST:
 In certain cases police are not authorized to hold inquest and
magistrate himself will hold the inquest.
 Its superior to police inquest, as magistrate himself conducting, can
summon any person for enquiry and himself sends the body for
postmortem.
1. All dowry related death or death of a married women less than seven
years of marriage.
2. Deaths under police custody.
3. Deaths in police firing.
4. Death of a convict or under trial prisoner in jail.
5. Death in borstal school or reformatories.
6. Death in psychiatric hospital.
7. Exhumation.
Coroner’s Inquest:
 This inquest is held by the coroner, who was the specially appointed
state government.
 An officer entrusted with the duty of enquiring into all unnatural
death and suspicious cases.
 Coroner used to be a person with legal qualification of First Class
Magistrate
 This system was first implemented in England in 1275.
 This system was present at Kolkata and Mumbai previously. This
system has now been abolished from India but still present in England
and in certain European countries.

MEDICAL EXAMINER’S SYSTEM:
 In this type of inquest, Doctors having qualification in pathology, legal
medicine are appointed to the post of medical examiner.
 He will visit the crime scene, prepare inquest, conduct postmortem
examination and prepare the report. As both enquiry and PM are
done by medical professional, it is far superior but he lacks judicial
powers.
 This system is in practice in some states of U.S
Courts in India:
Civil courts:
 Family courts
 Labor courts
 Motors accident claims tribunal
 Consumer protection forum
 Administration tribunal
Criminal courts:
 Supreme Court.
 High court.
 Sessions court.
 Magistrate court.
SUPREME COURT:
• It is the highest judicial tribunal, present in New Delhi
• It has following powers
1. ORIGINAL JURISDICTION
2. APPELLATE JURISDICTION
3. ADVISORY JURISDICTION
4. CONCURRENT JURISDICTION
Original jurisdiction
- Disputes between govt. of India and state govt.
- Disputes between any two or more state govt.
- Arbitrator of election disputes relating to president and Vice-
president of India.
APPELLATE JURISDICTION
- Criminal appeals in cases given verdict by lower courts.
- Civil appeals if the value of the disputed subject matter
is more than 20 lakhs.
ADVISORY JURISDICTION
- The president can refer any question of law or opinion of fact to
Supreme Court.
CONCURRENT JURISDICTION
- This court has got concurrent jurisdiction with high court.
HIGH COURT:
 It is the highest court of judiciary in the state.
 It has the following powers
o APPELLATE JURISDICTION
o CONCURRENT JURISDICTION
 It is the highest appellate in both civil and criminal matters in
state.
 All death sentence given by any sessions court has to be
corroborated by high court.

SESSIONS COURT:
 It is established in every district.
 It is presided over by a session’s judge appointed by high court.
 It can pass any sentence of law except death sentence which has to be
confirmed by high court.
COURTS OF MAGISTRATE:
There are three of magistrates.
o CHIEF JUDICIAL MAGISTRATE
o FIRST CLASS MAGISTRATE
o SECOND CLASS MAGISTRATE
CHIEF JUDICIAL MAGISTRATE:
Chief of all other 1st& 2 ndclass magistrate of the district
- He can try any case except those of murder, rape, dacoit,
Criminal abortion.
Can pass
- Sentence of imprisonment not more than 7 years.
- Unlimited amount of fine.
FIRST CLASS MAGISTRATE:
- He can pass a sentence of imprisonment not more than 3 years
- He can impose fine not more than Rs. 10,000/-
SECOND CLASS MAGISTRATE:
- He can pass a sentence of imprisonment not more than 1 year
- He can impose fine not more than Rs. 5000/-
All judicial magistrates can impose both fine and imprisonment for any
number of times.
Punishments Authorized In India:
1. Capital punishment
Death sentence by hanging
2. Life imprisonment
Usually for 20 years, can be reduced to 14 years on good behavior.
3. Imprisonments
Simple – no hard labor
Rigorous – with hard labor
Solitary – in isolation not more than 3 months
4. Fine
Attachment of property
Detention in reformatories
Evidence:
It any oral statement or document of a witness recorded and accepted in
the court of law, under oath, relating to a particular fact under enquiry
Classification of Evidence:
Outside court
How the evidence was acquired by the witness
 Direct
 Indirect
Inside court
How the evidence was presented in court
 Oral
 Document
1. Direct evidence
The witness has directly seen the crime or felt it by any of his senses.
2. Indirect evidence
a. Circumstantial
Witness has not directly seen the crime but has seen several related
things which point strongly towards the commission of crime.

It is admissible in court until the connection is too weak to prove the
commission of crime.
b. Hearsay
Witness only heard about the crime from someone.
Generally not admissible exception – Dying declaration
1. Documentary evidence:
All documents that are produced in the court of law including
electronic records, in which matters are expressed by means of letters, marks
or figures.
Documentary Evidence in relation to medical Practice:
1.Medical certificates
2. Medico legal reports
3. Dying declaration
Medical certificates:
1. Sickness certificate
2. Physical fitness certificate
3. Birth and death certificate
4. Age certificate
5. Insanity certificate
6. Vaccination certificate
7. Disability certificate
Medico legal reports:
a. Wound/ injury report
b. Drunkenness certificate
c. Impotence/ sterility certificate
d. Post mortem report
e. Chemical examiner report
f. Ballistics report
Dying declaration:
 It is a statement, verbal or written made by a person who is dying
as a result of some unlawful act.
 It is relating to the cause of death or any other circumstances that
has resulted in his death
 Should be recorded by a magistrate in the presence of a doctor
and two witness.
 In the absence of magistrate if the patient condition is worse, then
doctor himself can record the evidence with two witnesses.
 Patient should be in sound state of mind
 No oath necessary
Dying deposition:
Statement made by a dying person under oath and recorded by a
magistrate in the presence of the accused and his lawyer.
 Oath is necessary
 Cross examination is allowed
 Bed side court
 Its practice is not allowed in India
Oral Evidence:
 All verbal statements under oath made before the court which it
records in relation to a fact under enquiry.
 It is more important than documentary evidence as cross
examination by opposite party is allowed.
 Moreover all documentary evidence has to be verified orally
before acceptance in the court of law. Except in following
conditions.
Exceptions to oral verification of documentary evidences:
1. Dying declaration
2. Expert opinion in treaties ( accepted textbooks)
3. Medical evidences recorded in lower court
4. Evidences given by a witness in previous judicial proceedings

5. Reports of government scientific experts
Chemical Examiner, Inspector of Explosive, Finger Print Bureau.
6. Public records
Birth Certificate, Death Certificate, Marriage Certificate.
7. Hospital Records
Case Files, Investigation Records, Discharge Summary.
Witness:
 Is a person who gives evidence in the court of law under oath.
 All persons can give evidence unless they can’t understand the
question and give rational answer due to tender years of age or old
age or disease.
Types
o Common witness
o Expert or skilled witness
o Hostile witness
Common witness:
 Is a common man who gives evidence about a fact, what he has
seen or perceived.
 He will not give any inference from what he has observed.
Expert or Skilled witness:
 Is one who has acquired special knowledge, skill or experience in
any science, art or profession
 He not only gives evidence of fact what he has observed
 But also capable of giving certain inference from the observation
he has made.
 A medical profession can be a common witness and an expert
witness.
Perjury:
The act of wilfully giving false evidence in the court of law under oath
is called Perjury and he is punishable under section 193 IPC.
Hostile witness:
Hostile witness is a witness who in the court if conceals a part or
whole of truth and gives an evidence against the party that has called the
witness.
Summons or Subpoena:
 It is a written order issued by the court to a witness compelling his
attendance to give evidence under penalty in the court on a specific
date, time and place.
 Non-compliance without valid excuse is punishable.
In case of two summons on same date:
Civil court Vs Criminal Court - Importance to Criminal Court
Courts of same type - Importance to court of higher rank
Courts of same type & Rank - Importance to earlier received summon
Proceedings in court:
After oath taking
1. Examination in chief
2. Cross examination
3. Re examination
4. Questions by court
1. Examination in chief:
 Here the witness is examined by the lawyer of the party who has
summoned the witness
 Purpose is to bring out all the facts known to the witness and
relevant matters in the court of law
 No leading questions are allowed in examination in chief.
2. Cross examination:
 Here the witness is examined by lawyer of opposite party.
 Purpose is to test the reliability and truthfulness of the witness
and his evidence.

 The lawyer of opposite party will try to weaken the evidence given
in the examination in chief.
 Leading question are allowed in this stage
3. Re Examination:
 The witness is re-examined to clarify any doubt arisen during cross
examination
 The witness gets a second chance to correct himself here
 Leading questions are not allowed
 No new matter or fact can be brought in the re-examination.
4. Questions by Court:
 The judge can ask any questions at any point of time to clear any
doubt arisen.
 The court may recall the witness and re-examine him who has
been already examined if it is essential
 The witness has to read the recorded deposition made by him and
sign it before leaving the court.
Duty of doctor in court of law:
 Be well prepared
 Have all documents
 Do not memorise
 Well dressed and modest
 Speak audibly, clearly
 Simple language, no technical terms
 Do not exaggerate
 Do not fumble
 Do not discuss the case other than lawyer
 Address judge respectfully
 Avoid discrepancies with previous statements.
 If a question is not clear ask to be repeated.
 If you don’t know the answer admit it
 Do not lose your temper
 Do not Argue, Disagree firmly
 Be brief and precise
 Express opinions only on the basis of your knowledge and
experience
 Be honest
 Be absolutely impartial

2.Medical Law and Ethics
Indian medical council:
Members
1. One member from each state
2. One member from each state medical council
3. One member from each medical university
4. Eight members from central government
 President, vice President and Register will be elected
 Tenure for office is Five years.
Functions of Indian Medical Council:
1. Medical Register
 Contains names of medical persons who registers
with MCI or with any state medical council, who
possess a recognized medical qualification.
 Names are usually erased at the death of the
member
 Names can be erased temporarily or permanentlyon
disciplinary actions when found to be guilty of
unethical practice.
2. Maintenance of standards of Medical Education
 Undergraduate&Post graduate Medical education
o Maintaining standards and uniformity
o Recommendation to central government for
starting new medical college/ new medical
course/ increase of seats
 Inspection of Medical colleges
o For every introduced medical qualification
(MD/MS/DM/Mch/Diploma)
o For routinely every 5 years to determine
standards, training, staffs and facilities.
3. Recognition of Foreign Medical qualifications
o First Schedule:
 Contains recognized medical qualification
granted by university of India.
o Second schedule:
 Contains recognized medical qualification
granted by university outside India.
o Third schedule part 1:
 Contains recognized additional medical
qualification granted by university of India.
o Third schedule part 2:
 Contains recognized additional medical
qualification granted by university outside
India.
4. Disciplinary Action
o Excercises disciplinary control over members of medical
profession.
o It acts as an advisory body of central government for
appeals by medical profession against actions by state
medical council.
o It issues warning notice periodically

o It’s a list of offences considered to be unethical
practice- infamous conduct/ professional
misconduct.
State medical council:
1. Maintenance of State Medical Register
• Registered medical practioners name and
qualification
• Date of registration
• Annual update to medical council of India
2. Disciplinary Action
• Investigation of various accusation of professional
misconduct.
Punishments:
1. Warning:
A warning is issued to the medical practioner to conduct
himself according to the ethical standards.
2. Temporary Erasure:
Name of medical practioner is erased from the register
temporarily and he is disqualified to practice medicine for a
specific period
3. Penal erasure:
Name of medical practioner is erased from the register
permanently and he is disqualified to practice medicine forever.
Also called as Professional Death Sentence.
Professional Misconduct:
Any act or behavior of a Doctor which is considered disgraceful
or dishonorable by his professional colleagues of good repute.
• Act or Behavior Medical Ethics
Disgraceful or Dishonorable
Professional Colleagues of Good Repute.
When such a behaviour complained to medical council, an
inquiry is done by an ethical committee comprising of team of
doctors from medical council and if found guilty any of the
following punishments can be awarded.
1. Warning
2. Temporary removal of name from the register
3. Permanent removal of name from the register - Penal
Erasure
1. Abortion:
Illegal termination of pregnancy – that is terminating
pregnancy against rules laid by The Medical Termination Of
Pregnancy Act 1971 is considered as professional misconduct.
2. Adultery:
A medical professional must maintain highest standard of
moral integrity. He should not misuse his position to commit
adultery with his patients, relatives or attendants.
3. Alcohol:
Attending the patients under influence of alcohol is
considered as professional misconduct.
4. Advertisement:
The following acts are considered as professional
misconduct.

• Giving interviews about disease in such way to advertise
his personal achievements in surgery or medical treatment.
• Having large sign board of advertisement
• Publicly displaying his fees except in consultation room
5. Addiction to narcotic drugs:
As a medical practitioner, he can get access to various
kinds of drugs. A doctor can be charged with professional
misconduct if he misuse his access to drugs and gets addicted
to it.
6. Association with unqualified persons:
The following acts are considered as professional
misconduct.
 Association with unqualified persons to promote one
practice
 Engaging unqualified persons in technical positions
 Dichotomy or fees splitting – giving or accepting
commissions from colleagues, agents, manufacturing
agents for personal gain.
 Accepting gifts, travel facilities from pharmaceutical
companies.
Medical Negligence:
• Negligence can be defined as doing something which a
prudent and reasonable man would not do or omission to
do something which a reasonable man would do.
• Medical negligence is defines as absence of reasonable
knowledge and skill or wilful failure in exercising due care
in the treatment of a patient which results in bodily injury
or death of the patient.
• When deviates from accepted practicesor
• When employs accepted practices but does it
unskilfully
Factors Necessary to prove medical negligence:
1. Duty of Care
2. Dereliction of Duty
3. Damage
4. Reasonable Foreseeability of Doctor
1. Duty of Care:
• The doctor must be under a duty of providing care to
the patient.
• Even if doctor is not charging any fees for consultation
also he is bound to duty of care.
• Even in an emergency condition like in causality, if
doctor sees a patient then he is under duty of care.
• But if a Doctor act as a ‘Good samaritan’ helping some
injured person at roadside then he is not bound to Duty
of Care
2. Dereliction of Duty:
• Failure of a doctor to honour his duty that is owed to
his patient is referred to as dereliction.
• Failure on the part of doctor to maintain skill and care
has to be proved.
• Not highest degree of skill or knowledge, But skill and
knowledge of ordinary competent doctor

• Error of Judgement either in diagnosis and treatment is
not considered to be negligence.
3. Damage:
• Damage refer to injury or disability suffered by the
patient.
• Failure to exercise a duty of care must lead to actual
damage to the patient.
• If no damage has happened, then, though there is
negligence the doctor can’t be sued.
• A causal relationship has to be proved that dereliction
of duty has caused damage to the patient.
4. Reasonable Foreseeability of Doctor:
• The inability of a doctor to predict an injury in future
which a reasonable doctor would have predicted is also
considered to be Medical negligence
Types of negligence:
1. Medical negligence
a. Civil negligence
b. Criminal negligence
2. Patient negligence
3. Contributory negligence
4. Composite negligence
5. Corporate negligence
1. Civil negligence
Is said to occur when the damage caused was generally
minor and patient demands for monetary compensation
for the damage that he has suffered due to doctor’s
negligence.
• Court: civil court or consumer forum.
• Punishment:only monetary loss have to bepaid. No
criminal liability so cannot be sent to jail.
• Burden of proof: it is the duty of patient to prove
negligence.
2. Criminal negligence
Is said to occur when the damage caused is generally
gross and the patient complains of doctor’s negligence to a
police and registers a case in criminal court.
• Court: criminal court.
• Punishment: criminal liability under various IPC
sections.
• Burden of proof: it is the duty of doctor to prove that
he is not negligent and proof of negligence should be
beyond doubt.
3. Patient negligence
The negligence is in patient’s part.
It is a good defence for doctor in cases of civil
negligence and not in criminal negligence
1. Not revealing previous history
2. Not following instructions given by doctor
3. Discontinuing the treatment
4. LAMA- leaving hospital against medical advice.
4. Contributory negligence:

 Both patient and doctor are negligent. It’s a
defence in civil negligence cases only.
 Quantum of injury caused will be assessed
according to the amount of negligence of patient
and doctor and compensation is awarded
accordingly.
Example: doctor prescribes a drug without informing about
side effects and patient not following instructions given by
doctor.
5. Composite negligence:
 When the patient has suffered injury due to
negligence of two or more than two doctors then it
is called composite negligence.
 The patient can claim compensation from each
doctor or from any single doctor he wishes as he
wishes
6. Corporate negligence:
It is the negligence of corporate – hospital and not of a
doctor who is working there.
 Defective or poorly maintained equipment
 Selecting incompetent employees
 Lack of electricity back up in operation theatre
 Not maintaining sterile OT.
Important Concepts of Medical Negligence:
1. Vicarious Liability
2. Borrowed Servant Doctrine
3. Res Ipsa Loquitur
1. Vicarious Liability:
Captain of ship doctrine:
 When the superior had the right, ability or duty to
control the employee working under him, then he is not
only responsible for his negligent acts but also of his
employee’s negligent act.
 Only If the negligent act happens in the course of
employment and within its scope.
Conditions to be satisfied:
Employer – employee relationship should be
established
Employee negligent conduct should be within the scope
of his employment
Senior doctor is also responsible for negligent acts by junior
doctor, intern or trainees.
2. Borrowed Servant Doctrine:
 If an employee is borrowed by a temporary employer
from a principle employer then the new employer is
vicariously liable for the negligent acts of the employee
 It is the duty of the new employer to check the
competency of the employee.
 New master is responsible for the employee only when
he works under his own supervision.
3. RES IPSA LOQUITUR:
 It means the thing speaks for itself.

 Usually in a case of medical negligence, the patient has
to prove it. But when the negligence is so gross, then
the rule of Res Ipsa Loquitur applies and the patient
need not to prove it..
 Conditions to be satisfied:
 Injury to the patient would not have happen in the
absence of negligence.
 The doctor had complete control over the injury
producing instrument or treatment.
 Patient is not guilty of contributory negligence.
Examples:
1. Prescribing overdose of a medicine
2. Failure to remove swaps from abdomen after a
surgery
3. Amputating wrong digit of a foot
Defences against negligence:
1. No duty owed by doctor – Good Samaritan
2. Patients negligence
3. Calculated risk doctrine
4. Novus actus intervenes
5. Medical misadventure
6. Products liability
7. Res limitica
8. Res judicata
1. No duty owed by doctor – Good Samaritan:
 If a Doctor act as a ‘Good samaritan’ helping some
injured person at roadside then he is not bound to
Duty of Care. And the doctor can’t be charged of
medical negligence in such cases.
2. Patients negligence:
 If the patient is negligent in his part then,it is a good
defence for doctor in cases of civil negligence and
not in criminal negligence.
3. Calculated risk doctrine:
 All medical treatment will have certain side effects
and as a doctor to save the life of patient he has to
take certain risk - Calculated risk doctrine.
 A doctor is not liable of medical negligence, if he has
taken a reasonable risk to save the life of a patient
and in the process if the patient suffers any injury.
Example:
1. Amniocentesis: has 0.1% of mortality to foetus
2. CPR: fracture of ribs
4. Novus actus intervenes:
 An unrelated action intervening.
 Refers to a situation where the doctor is negligent, but
a completely unexpected and unforeseen act happened
that has resulted in injury, death or worsening of the
patient condition.
 The new act has to be unexpected and unforeseen
breaking the chain of causation then the doctor can’t be
charged of medical negligence in such cases.
5. Medical misadventure:

 Is defined as a case where the patient suffered injury or died
due to unintentional act of the doctor/hospital
 It is due to undesirable outcome that is unrelated to the
quality of care provided.
 Therapeutic misadventure: when a serious allergic reaction
happens to common drug given in the absence of any
significant allergic history.
 Diagnostic Misadventure: when a diagnostic procedure
carried on and an unexpected injury could happen
irrespective of all precautionary measures.
 The doctor can’t be charged of medical negligence in such
cases.
6. Products liability:
 The injury or death of a patient may be due to
 Faulty, defective or negligently designed
instruments/ equipment
 Drugs that are adulterated, contaminated or of
inferior quality.
 In such cases, the manufacturer is responsible for the harm
caused except in following cases.
 Doctor/hospital misused the equipment
 Instrument was functioning well at the time of
supply and now malfunctioned due to improper
use, not serviced regularly, not maintained
properly
7. Res limitica:
 A suit for damages by negligence of a doctor should be
filed within two years of time from the date of alleged
negligence.
 A suit filed after two years will be dismissed as
being beyond the period of limitation.
8. Res judicata:
 The thing is already been decided.
 If a question of negligence is already been decided in a court
then the patient will not be allowed to file same negligence
case in another proceedings on same set of facts.
 Appeal against in a higher court is allowed.
Consent:
 It is a Voluntary agreement / Compliance / Permission for a
specified act…
 To be valid it should be intelligent and informed….
 Means it should be given after understanding for what it is
given and after acquiring the knowledge of risk involved
Types:
1. Implied consent
• It is indicated by manner and behaviour of the patient.
• It is adequate for general examination of a patient.
• For any special examination, diagnostic procedure, surgical
intervention, informed consent is must.
2. Informed consent
• It is consent given by a person after the receipt of
information for the specified act.
• Oral
• Written
Components of consent:
 Free
 Voluntary

 Under sound mind
 Informed
 Clear and direct
 Whenever possible it should be in written form
Information that should be provided:
 Nature and purpose of the proposed procedure or
treatment
 The expected outcome and the likelihood of success
 The risks involved and its likelihood to occur.
 The alternatives to the procedure and supporting
information
 The effect of no treatment or procedure and on prognosis
 Instructions regarding what should be done if the
procedure turns out to be harmful and unsuccessful.
Criteria for giving consent:
• Age should be more than 12 yearsto give consent for special
examination and diagnostic procedures
• Age should be more than 18 years to give consent for any
surgical procedures or treatment procedures.
• If the patient doesn’t met with the age requirements then
consent has to be taken from parents or legal guardians.
• Doctrine of loco parentis:
• In the case of absence of parents or legal guardian,
whoever in charge of the patient can act as legal
guardian or as local parents and give consent for the
specified act
Failure to get consent:
• Any doctor should examine or treat a patient after
informing the necessary things and getting a consent from
them, if not the treatment or examination done will be
deemed to be intentional interference with the patient’s
body without his sanction.
• This is in turn amounts to assault to the patient.
• For which the patient can charge you with medical
negligence.
EXCEPTIONS:
1. Therapeutic privilege:
In some cases the doctor may withhold some of the
information without revealing to the patient if he believes that
disclosure can cause psychological harm to the patient or it may
lead to discontinuing of treatment by the patient. This is called
as Therapeutic privilege.
In such a situation also the doctor has to document all
information and reason for withholding the information in the
case records.
2. Extension doctrine of consent:
 The patient has given consent for a specified procedure
and during the procedure if the doctor is confronted
with unanticipated condition requiring immediate
action to save the life of the patient then he is justified
to carry on with that procedure without getting
separate consent.
 This is referred to as the extension doctrine of consent.
3. Other exceptions:
 The patient is in coma and needs emergency treatment
 The patient is a child and needs emergency treatment
and parents are not immediately accessible.
 When a medico legal case is referred by court of law
for examination

 Consent of spouse is not necessary in procedures
involving no genital organs or affecting reproductive
function.
Consent in medico legal cases:
Consent for examining a person brought by police:
• The patient has to be informed about the nature of procedure,
the purpose of procedure and the consequences.
• He has the right to refuse the examination and the report may
go in his favour or against him.
Consent for examining a person arrested by police:
• If a person is arrested for charge of any crime then he loses his
right to refuse the examination. He can be examined without
his consent.
Professional secrecy:
• During the course of treatment a patient may reveal matters of
personal nature to doctor which he is obliged to maintain it as
secret until requested by law to divulge it or when the patient
consented for divulging it.
• In case of domestic servants, the details are not be shared to
his master, even though the master is paying the fees
• In case of prisoners, the details are not be shared toto the
Jailers
Exception:
• Minor
• Mentally insane
• Intoxicated person
Privileged communication:
• It is a statement made by a person to another person having a
corresponding interest, even though such communication may
under normal conditions amount to defamation.
• The doctor can divulge the information in certain conditions
this is called privileged communication.
Examples:
1. Of public interest:
The communicable disease of a labour working in a
restaurant can be shared to appropriate authority to
control the spread of disease.
2. Of relatives interest:
If either of spouse suffering from veneral disease,
then it can be shared with other spouse for necessary
precautions to avoid spread of it.
3. Under law:
The details of a patient have to be shared in court of
law if asked by the judiciary department.
Rights of a Doctor:
1. Right to practice anywhere in India
2. Right to add professional titles and qualification to name
3. Right to choose patients
4. Right to prescribe and dispense medicines
5. Right to issue birth, death, sickness, insanity certificates
6. Right to give evidence as an expert evidence
7. Right to possess, dispense and prescribe drugs listed in
dangerous drugs Act
8. Right to claim payment of fees for professional service
rendered.

3.DEATH & ITS MEDICO-LEGAL
IMPORTANCE
Definition:
Registration of Births and Deaths Act, Sec.2(b) defines death
as ‘Permanent disappearance of all evidence of life at any
time after live birth has taken place’
TYPES OF DEATH:
1. SOMATIC DEATH: -
 It is complete and irreversible stoppage of circulation,
respiration and brain functions.
 The individual will never again communicate or
deliberately interact with the environment and is
irreversibly unconscious and unaware of both the
world and his own existence.
2.CELLULAR DEATH: -
 The cessation of utilization of oxygen and the normal
metabolic activity in the body tissues and cells is
known as cellular death.
 Different internal organs with different function and
with different metabolic rate have different rate of
cessation.
 Hence death is a process of cessation of different
internal organs which proceeds from somatic death/
systemic death to cellular death.
BRAIN DEATH: -
 Brain death is the irreversible end of all brain
activityincluding involuntary activities necessary to
sustain life.
TYPES OF BRAIN DEATH: -
1. Cortical death
 If the cerebral cortex of brain alone is damaged, the
patient passes into deep coma, but the brain stem
will maintain spontaneous respiration.
 This is called “persistent vegetative state” and death
may occur months or years later due to extension of
cerebral damage
2. Brain stem death
 If the brain stem is damaged due to various causes,
 Respiratory motor system fails &
 Damage to the ascending reticular activating
system - permanent loss of consciousness,
 Ultimately lead to whole brain death.
3. Whole brain death: - cortical + brain stem death

Various criteria for diagnosis of death:
Philadelphia Protocol (1969)
1. Lack of responsiveness to internal and external
environment.
2. Absence of spontaneous breathing movements for 3
minutes, in the absence of hypocarbia and while
breathing room air.
3. No muscular movements with generalized flaccidity
and no evidence of postural activity or shivering.
4. Reflexes and responses:
a. Pupils fixed, dilated, and nonreactive to strong
stimuli,
b. Absence of corneal reflexes.
c. Supraorbital or other pressure responses absent
d. Absence of snouting and sucking responses.
e. No reflex response to upper and lower airway
stimulation
f. No ocular response to ice-water stimulation of inner
ear.
g. No superficial and deep tendon reflexes.
h. No plantar responses.
5. Failing arterial pressure without support by drugs or
other means.
6. Isoelectric EEG (in the absence of hypothermia,
anesthetic deaths, and drug intoxication) recorded
spontaneously and during auditory and tactile
stimulation.
All these criteria should be present
- at least for 2 hrs&
- certified by two physicians other than involved in
organ donation.
MINNESOTA CRITERIA
1. Known but irreparable intracranial lesion.
2. No spontaneous movement.
3. Apnoea when tested for a period of 4 minutes.
4. Absence of brain stem reflexes:
i. Dilated and fixed pupils,
ii. Absent corneal reflexes,
iii. Absent doll’s head phenomenon,
iv. Absent cilio-spinal reflexes,
v. Absent gag reflex,
vi. Absent vestibular response to caloric
stimulation,
vii. Absent tonic neck reflex.
5. EEG not mandatory.
6. Spinal reflex not important.
All the findings above remain unchanged for atleast 12
hours.

HARVARD CRITERIA
1. Unreceptivity and unresponsivity:
2. Apnoea tested for 3 minutes.
3. Absence of elicitable reflexes:
a. -The pupils - fixed and dilated and don’t respond
to bright light.
b. -Ocular movement and blinking - absent.
c. -No evidence of postural activity.
d. -Corneal and pharyngeal reflexes - absent.
e. -Stretch tendon reflexes – absent.
4. Isoelectric EEG: - It is confirmatory.
All these tests should be repeated after 24 hours with no
change.
DIAGNOSIS OF BRAIN STEM DEATH:-as per THE
TRANSPLANTATION OF HUMAN ORGANS ACT,1994
Exclusions:
1. Under the effects of drugs, e.g. Therapeutic drugs or
overdoses.
2. Core temperature of the body is below 35°c.
3. Severe metabolic or endocrine disturbances which may
lead to severe but reversible coma, e.g. Diabetes.
Preconditions of diagnosis:
1. Patient must be deeply comatose.
2. Patient must be maintained on a ventilator.
3. Cause of the coma must be known.
Personnel who should perform the tests:
1. By two medical practitioners.
2. Doctors should be experts in this field and not
performed by transplant surgeons.
3. At least one should be of consultant status. Junior
doctors are not permitted to perform these tests.
4. Each doctor should perform the tests twice.
TESTS to be done:
1. Pupils are fixed in diameter and do not respond to
changes in the intensity of light.
2. There is no corneal reflex.
3. Vestibulo -ocular reflexes are absent, i.e. no eye
movement occurs after the instillation of cold water
into the outer ears.
4. No motor responses within the cranial nerve
distribution for painful stimuli.
5. There is no gag reflex to bronchial stimulation.
6. No respiratory movements occur when disconnected
from the ventilator for long enough to ensure that the
CO2 concentration in the blood rises above the
threshold for stimulating respiration, i.e. after giving
the patient 100% oxygen for 5 minutes.
Two doctors have to performed all these tests twice.

4.AUTOPSY
Postmortem examination:
It is also called as Autopsy or necropsy. It is defined as
Investigative dissection of dead body. 1st autopsy done by
DrAmbroise Pare on King Henry II.
Objectives:
1. What are the injuries – Documentation of injuries
2. When injuries occurred – Time since injury occurred
3. Why were the injuries produced – Manner of death
4. Which injury caused death – Fatal injury
5. When death occurred – Time of death
6. Who is the victim - Identification
7. How the victim died – Cause of death
Secondary objectives:
1. Evidence collection
2. Reconstruction of event
3. Fetus :
a. Age and viability
b. Live birth or dead born
Types:
1. Medicolegal Autopsy
2. Clinical Autopsy
3. Psychological Autopsy
4. Endoscopic Autopsy
5. Virtual Autopsy
1. Medicolegal Autopsy:
 Done in suspicious cases, sudden death, unnatural deaths,
and criminal death.
 On request by an investigating officer.
 So requisition letter is a must.
 Consent of legal heirs is not necessary.
2. Clinical Autopsy:
 Done In death due to natural causes
 For academic purpose/research
 To ascertain the exact cause of death
 To confirm or refute the diagnosis
 Consent of legal heir/close relative is a must
 Requisition from investigating officer is not needed
3. Psychological Autopsy:
 It is retrospective study of events of deaths
 Done in cases of suicide to find out whether the person was at
high risk of committing suicide or not.
 Analyzing medical records, personal history,
 Analyzing crime scene, suicide notes.
 Interviewing all close associates to get vital information.
4. Endoscopic Autopsy:
 It is an alternative to traditional autopsy
 When fatal injury is confined to abdominal organs, Postmortem
endoscopic examination with trocar and telescopic device to
find out the exact cause of death.
5. Virtual Autopsy:
 Replacing traditional Autopsy.
 Using various modern cross sectional imaging techniques to
find out the cause of death
 CT, MRI, Postmortem X rays etc.

 3 Dimensional reconstruction of CT images to arrive at the
conclusion.
Procedure of Autopsy
1. External Examination
2. Internal Examination
External Examination:
a. Identification
• Age, Sex, Weight, Height, complexion
• Nutritional status, deformities, hair
• If Unknown - details of clothes, moles, scars
• Fingerprints, photographs of the body
• Bone/ teeth for DNA analysis
b. Coverings of body
 Wrappings of body
 Hospital dressings
 Clothing
o Loss Of Buttons
o Cuts And Tears
o Firearm Injuries – Burns Or Blackening
o Characteristic Odor
o Stains In Clothing
 Blood, Semen, Saliva
 Vomit, Poison, Vitriolage
 Feces, Mud, Grass
c. Examination of body:
 Head to toe examination
 Any deformity
 Signs of diseases, pallor, jaundice
 Status of natural orifices
 Traces of blood, semen, saliva
 Characteristics of odor
 Documentation of injuries
d. Estimation of time since death:
 Hospital records
 Status of eyes
 Postmortem lividity
 Rigor mortis
 Features of decomposition
 Rectal temperature
 Entomology activities
Internal examination:
Various incisions:
1. I incision:
– From chin to pubic symphysis with deviation to
umbilicus
- Skin reflected laterally
2. Y shaped incision:
-From behind each ear from mastoid to extend down to
sternal notch and downwards to pubic symphysis
3.Modified Y Shaped Incision:
- Starts below anterior axillary folds andthen extends
below breasts meets at xiphisternum and then extends
down to pubic symphysis.
4. T shaped incision:

- From acromion process to suprasternal notch and then
downwards to pubic symphysis.
5. Cosmetic autopsy incision:
- To avoid disfigurement.
Techniques of organ removal:
1. Virchow Method
 After opening up the cavities, the organs are removed
one by one.
Advantage:
 Quick and Easy
Disadvantage:
 Inter Relationship Lost,
 No Continuity between Organs
2. Rokitansky Method
 In situ dissection
 Done in highly contagious cases
 In pediatric cases
Advantage:
 In children,
 Infected bodies
Disadvantage:
 Difficult In Adults
3. Ghon method:
 Also called as en bloc removal
o Thoracic bloc
o Intestinal bloc
o Coeliac bloc
o Urogenital bloc
Advantage:
 Preservation of organsexcellent
Disadvantage:
 If disease extends beyond bloc then Inter
relationship Lost.
4. Letulle Method:
 Also called En masse removal.
 Cervical, thoracic, abdominal, and pelvic bloc are
removed in one mass
Advantage:
 Excellent preservation of organs and inter relationship
with their lymphatic drainage.
Disadvantage:
 Difficult in handling the organs as en mass
Negative autopsy:
At the end of a complete and thorough post mortem examination,
inclusive of all relevant investigation such as histopathological, toxicological
and biochemical examination, if the cause of death of the deceased could
not be ascertained, then such an autopsy is termed as “Negative or Obscure
Autopsy”.
Approximately 2 to 5% of all autopsies are negative in nature.
Causes:
1. Inadequate history
2. Natural diseases which is difficult to establish as a cause of autopsy
like cardiac arrhythmias, uraemia, adrenal insufficiency
3. Death due to vagal inhibition
4. Death due to anaphylaxis
5. Death due to certain kinds of poisons like anaesthetics, snake bites

5.Post Mortem Changes
Signs of Death & Postmortem changes after
death:
1. Immediate Changes
2. Early Changes
3. Late Changes
Immediate Changes:
Permanent Cessation of Brain function.
Complete Cessation of Circulatory function.
Permanent cessation of Respiratory function.
Suspended Animation
It is a condition in which the metabolic needs and vital
functions of the body are reduced to such a low level that
they can’t be appreciated by clinical examination and the
person appears apparently death.
Such persons are actually not dead and can be revived
by resuscitation.
Features:
1. Pulse is not palpable,
2. Heart sounds not audible,
3. Respiratory movements are not visually perceptible
and
4. Reflexes are either absent or not possible to elicit
Examples:
1. Voluntary- by yogis
2. Involuntary – drowning, electrocution, heat stroke,
typhoid fever, new born hypothermia etc.
Early Changes:
1. Changes in the eye
2. Changes in the skin
3. Cooling of the body/Algor mortis
4. Post mortem lividity/Hypostasis
5. Rigor mortis/Cadaveric rigidity
1. Changes in the eye:
1. Opacity of cornea
 Cornea becomes opaque in 6 hrs - Dry, Cloudy and
opaque
 Cornea can be harvested within this six hour for
transplantation.
2. Sclera – Tache Noire
If the eyelids are left open, desiccation of sclera
occurs leading to triangle shaped brownish discoloration
of areas on either side of cornea known as Tache Noire
3. Flaccidity of eyeball:
 Intra Ocular tension falls, eye balls become flaccid and
sinks.
 Normal IOP is 15 – 20 mm hg; after 2 hrs – 12 mm hg, 3
hrs - 10 mm hg, 4 hrs – 8.5 mm hg, 8 hrs – 5 mm hg

4. Pupils:
 Fully dilated in the early stage and constricted later due
rigor mortis of constrictor muscles.
5. Retinal:
 Blood flow in the retina becomes discontinuous and
segmented.
 This is known as rail roading phenomenon or
Kevorkian Sign
 The color of retina becomes pale after death and the
paleness increases with time.
2. Changes in the skin:
 Pale and Ashy white appearance
 Loss of Elasticity
 Lips become dry, brownish and hard due drying.
 Wounds will not gape if it is inflicted after death
 Wounds caused during life will retain their
characteristic features.
3. Cooling of the body/Algor mortis:
Cooling of the body after death due to
 Loss of thermo - regulatory mechanism of the
body which maintains the body temperature
 Imbalance between heat production and heat
loss.
 Loss of heat of body to surrounding till it
balances with environmental temperature by
means of
• conduction
• convection and
• radiation,
For the first two hours after death, there is some heat
production due to utilization of stored ATP molecules and
by anaerobic glycolysis.
Due to which
there is little or
no fall in body
temperature
during initial two
hours and then
rate of cooling is
fast during next
few hours and
later slows down.
Temperature is recorded by Chemical thermometer-
Thanotometer 25 cms inserted in anus.
Rectal temperature at the time of
death – Rectal temperature at the
time body found
Time since death = ---------------------------------------------
Rate of fall in temperature

Factors affecting rate of cooling:
1. Environmental temperature
Rate of fall of body temperature is faster in winter and
cold environment when compared with summer and
hot climate
2. Build / body surface area
Rate of fall of body temperature is faster in babies due
to larger body surface area per body weight compared
to adults
3. Physique / Fat Content
Rate of fall of body temperature is faster in persons
with lean body mass as body fat acts as a body heat
insulator.
4. Environment – Air, water
Rate of fall of body temperature is faster in body found
in free flowing water body compared to stagnant water
body as moving water reduces the body temperature
5. Position of body:
Rate of fall of body temperature is slower in body
which lies in curled up position as it reduces the loss of
heat to environment.
6. Coverings:
Rate of fall of body temperature is slower in body
covered with thick clothes.
Post Mortem Caloricity
Is a condition in which the temperature of body after
death instead of decreasing it increases.
Causes
 Body lying in open hot summers
 Infections – cholera, malaria, tetanus, typhoid
septicaemia
Temperature already increased at the time of
death
Metabolism of micro-organisms continuing
after death
Other causes:
 Strychnine poisoning
 Sun stroke
4. LIVOR MORTIS:
It is the reddish-purple discoloration of the most
superficial layer of the dermis due to accumulation of fluid
blood in the dependent area of body after death.
Other terms:
 Livor lividity, Post mortem Hypostasis, Post mortem
Staining
Suggillation, Lucidity, Vibices, Darkening of Death.
Mechanism of appearance:
 It occurs after death when circulation stops.
 When circulation stops, the blood gets stagnated.

 Gravity now acts on the stagnant blood and pulls it to
the lowest accessible areas.
Fixation of Livor mortis:
 Post mortem staining starts to appear as patches
within 1 – 2 hrs, the multiple patches merges with each
other by 4 – 6 hrs
 The gravitated blood coagulates and gets fixed to
surrounding tissues by 6 – 10 hrs.
 And thereby the post mortem staining is fixed by 6 hrs.
 Suppose
• If the body is changed to a new position within 6
hours of death, then the hypostasis patches
disappears and occurs in the new dependent
areas.
• If the body is changed to a new position after 6
hours of death, then the hypostasis stays in the
same original areas.
Distribution of lividity:
 Most commonly, when body lying on the back,
• It is present all over the back except over areas
of contact flattening, like occipital scalp,
shoulder blades, mid back, buttock, posterior
thighs, calves and heels wherein the tissue is
compressed by supporting bed preventing
accumulation to blood
 Prone position
• It is present in front of the body except,
forehead, nose, chin, cheek (if face is turned),
chest, lower abdomen, anterior thighs, knees and
toes points.
 Vertical position as in hanging
• It is seen most markedly in feet, legs and to
lesser extend in the distal parts of arms and
hands.
 If the body is seen in moving water like river
• The body is in constant change of position and
hence there will be no formation of hypostasis as
the body is not allowed to rest for gravitation of
blood to occur.
Color of hypostasis:
 It depends on the amount and state of hemoglobin of
the red cells.
a. Pink color:
• Death due to Hypothermia.
• Exposure to cold in agonal period.
• Refrigeration of body in mortuary
immediately after death.
The pink color of the hypostasis is due to oxygenated
hemoglobin.

b. Cherry Red color:
• Seen in cases of death by carbon monoxide
poisoning.
• Due to carboxy hemoglobin.
c. Brick red color:
• Seen in cases of death by cyanide
poisoning.
d. Brownish red color:
• Seen in cases of death by nitrate poisoning.
e. Dark brown or yellow color:
• Seen in cases of death by phosphorus
poisoning.
f. Pale bronze color:
• Seen in death by infection by clostridium
prefringens.
g. Greenish brown color:
• Seen in death by infection by clostridium
welchii.
h. Green color:
• Seen cases of death due to hydrogen
sulfide.
Medico-Legal Importance:
• It is a reliable sign of death
• Information about the position of the body at the time
of death
• Time since death can be estimated
• Color suggest the cause of death
• Distribution of lividity gives information about the
manner of death
Changes in the Muscles
1. Primary relaxation/ Flaccidity
2. Rigor mortis/Cadaveric rigidity
3. Secondary relaxation
1. Primary relaxation:
Starts immediately after death with generalized
relaxation of muscle tone:
• Drop of lower Jaw
• Eye balls lose their tension
• Pupils are dilated
• Joints are flabby
• Smooth muscle relaxation- incontinence of Urine and
Feces
2.Rigor Mortis/ Cadaveric rigidity
• It is generalized stiffening of the muscles of the body,
both voluntary and involuntary after death due to
formation of permanent actin myosin cross bridges.
• This phenomenon comes immediately after the
muscles have primarily relaxed.
Mechanism of development:
During alive, for contraction and relaxation of muscles,
• Calcium – required for formation of actin myosin
bridge -Contraction

• ATP - required for breaking the actin myosin bridge -
Relaxation
Immediately after death,
• Stored ATP is used – relaxed state of muscles in
Primary Relaxation
• Calcium stored in Sarcoplasmic reticulum- released
– actin myosin bridge formation – contraction of
muscles.
• Absence of ATP – no breaking of bridges –
formation of permanent actin myosin cross bridges.
• Generalized stiffening of all voluntary and
involuntary muscles.
Progression of rigor mortis:
• It starts in muscles around eyelids – facial and neck
muscles – muscles of trunk and upper limb – muscles
of lower limb – lastly in muscles of fingers and toes
• Rigor mortis disappears also in same order as it
appeared.
Time of Onset:
• Temperate climates – 3-6 hours
• Tropical climates – 1-2 hours
Duration it Lasts for:
• Temperate climate – lasts for 2-3 days.
• Tropical climate – 24 – 48 hours in winter
18 - 36 hours in summer
• In general In - 12 hours develops
For - 12 hours maintains
And - after 12 hours passes of
Circumstances modifying the Onset and
Duration of Rigor mortis:
1. Age-
 Rigor Mortis is very rare in premature
infants.
 Rigor mortis is slow in adolescence and
healthy adults
2. Muscular condition and activity before death-
• Onset is slow and duration is longer
• In muscular & healthy persons
• In dry and cold condition
• Onset is early and disappears soon.
• In wasting disease & great exhaustion- cholera,
plague, T.B, Cancer
• Warm and moist air condition
Conditions Simulating Rigor-Mortis:
1. Cadaveric Spasm:
Also called as instantaneous rigor, wherein only a
group of muscles which are active just before death go
into a state of sudden stiffens immediately after death
without the phase of primary relaxation.
Usually seen in cases of violent death as in
a. Drowning case – hand clutching grass and
weeds
b. Suicide by shooting – hand grasping the
gun tightly
Other conditions:
2. Heat Stiffening

3. Cold Stiffening
4. Gas stiffening in putrefaction
Late Signs Of Death
1. Decomposition / Putrefaction.
2. Adiopocere formation / Saponification.
3. Mummification.
1. Decomposition / Putrefaction
Last stage in the resolution of the body, from the organic
to the inorganic state resulting in softening & liquefying of
the body tissue.
Mechanism of autolysis:
• Rise of autolytic enzyme levels in the tissue cells after
death.
• Action of bacterial enzymes on tissue components –
carbohydrates/fat/proteins.
Characteristic features:
a. Colour changes:
• Greenish to black discoloration- ‘Sulph-meth-haemoglobin’
formed by H2S due to microorganisms in the large intestine.
• Greenish discoloration of skin over caecum and flanks – first
sign of post mortem.
• Discoloration spreads - front of abdomen, external genitals,
chest, neck, face, arms and legs – spreads whole body in 24-36
hrs.
• Discoloration of vessel walls due to pigmentation from
decomposed blood over the shoulder and groin. Arborescent
pattern- ‘Marbling’
b. GASES OF PUTRIFACTION
• H2S, ammonia, phosphate, CO2 and methane
• Under the skin and hollow viscera - 18-36 hrs.
• in solid viscera - 24-48 hrs.
• Causes pseudo rigidity, exerts pressure.
• More gases accumulation, body floats in water.
Pressure effects of putrefactive gases:
• Displaces the diaphragm upwards.
• Shifting of the area of hypostasis.
• Bloating of the abdomen, face and genital.
• Changes in appearance of genitals.
• Liquefied tissue mixes with gases producing froth
• Extrusion of fluid from the mouth and nose.
Insect activity- Entomology:
• After 18-36 hrs - Flies lay eggs over the decomposed
body- nose, mouth, vagina and anus.
• After 24-36 hrs - eggs hatch into larvae or maggots,
enter the body and destroy the tissues.
• After 4-5 days – maggot develop into pupae.
• After 7-8 days – pupae develop into adult fly.
Other changes following
• Fall of teeth
• Separation of skull sutures
• Liquefied brain matter oozes out.

• ‘Colliquative putrefaction’ – this process takes place
between 7-14 days.
Internal post-mortem changes
Early putrefaction - 24-48hrs
Larynx, trachea, brain of infants, stomach, intestines,
spleen, omentum and mesentery, liver and adult brain.
Late putrefaction - 2-3 weeks
Heart, lungs, kidneys, bladder, oesophagus, pancreas, diaphragm,
blood vessels, prostate, testis and non-gravid uterus, ovaries.
ADIPOCERE
• Modification of the process of putrefaction in the dead body is
(checked and is replaced) adipocere formation.
• Due to Hydrolysis of body fat into fatty acids.
• Forms saturated fatty acids - palmitic, stearic, hydroxyl-stearic,
olic acids with the help of Bacterial fat splitting enzyme
Lecithinase and moisture.
• Adipocere tissue has appearance of Yellowish white, greasy wax
with rancid smell.
• It forms at any site where fatty tissue is present.
Requirements:
• Time required, in summer-3 wks, in tropics-5 to 15 days.
• Humid climate & warm temperature
• Still air
• Bacteria producing fat splitting enzymes.
Medico legal importance:
• Facial features maintained – Identification
• Ante-mortem Wounds preserved – helps in finding
weapon and cause of death
MUMMIFICATION
• Another modification of the process of putrefaction in the dead
body is (checked and is replaced) Mummification.
• It is a peculiar type of dehydration of dead body where its soft
parts shrivel up but retain the natural appearance & the features
of the body.
• Rusty brown colour, dry, leathery skin adherent to bones.
• Internal organs get transformed into a thick brown mass.
Requirements:
• Time required - 3 months to 1-2 yrs
• Dry and hot climate.
• Free flowing air currents.
• Bodies buried in shallow graves, in dry sandy soils.
Medico legal importance:
• Facial features maintained – Identification
• Ante-mortem Wounds preserved – helps in finding
weapon and cause of death.
Time since death/ post mortem interval
• Important clue for investigation of time.
• It helps to apprehend the person likely to be involved.
Post mortem changes helpful to ascertain time since death
are;
a. -cooling of the body
b. -post mortem lividity
c. -rigor mortis
d. -decomposition changes
e. Contents of stomach and bowels
f. Contents of urinary bladder
g. Biochemical changes
h. Circumstantial evidence

6.MECHANICAL INJURY
Injury:
Legally under section 44 IPC, its defined as any harm
whatever illegally caused to any person in body, mind,
reputation or property.
Wound:
It includes any lesion, external or internal, caused by
violence, with or without breach of continuity of skin.
Legal Classification of Injuries:
1. SIMPLE INJURY - An injury which is not grievous is
simple
2. GRIEVOUS INJURY - According to Sec.320, IPC, any of
the following injuries
a. Emasculation
b. Permanent privation of sight of either eye
c. Permanent privation of hearing of either ear
d. Privation of any member or joint
e. Destruction or permanent impairing of the power of
any member or joint
f. Permanent disfigurement of the head or face
g. Fracture or dislocation of a bone or tooth
h. Any hurt which endangers life or which causes the
victim to be in severe bodily pain, or unable to follow
his ordinary pursuits for a period of 20 days
Classification of Mechanical Injuries:
1. Blunt Force Injuries/Trauma:
Abrasions,
Contusions,
Lacerations.
2. Sharp Force Injuries/Trauma:
Incised wounds,
Stab wounds,
Chop wounds.
3. Fractures.
4. Fire arm injuries.
Abrasion:
An abrasion is defined as loss of superficial layers of
skin or mucous membrane due to mechanical force.
Injuries involving superficial layers of the skin and are
caused by
-Impact of an object.
-Fall on rough surface.
-Pressure of finger nails, teeth, muzzle of a gun or
by rope.
Classification of abrasion:
According to direction of force

 Tangential abrasion – direction of force is
horizontal/tangential
1. Linear abrasion:
They are produced by horizontal or tangential friction
by the pointed end of an object sliding against the skin.
Thorn, needle, nail, tip of any weapon can cause such linear
abrasion.
2. Grazed abrasion/ Brush burns:
They are produced by horizontal or tangential friction
between boarder area of skin and object/ hard surface of
ground.
The epidermis will be heaped up at its end and the
pattern of heaping will indicate the direction of object
against the skin.
Usually seen in road traffic accidents where the
pedestrians will be dragged against ground for a distance.
 Compression abrasion – direction of force is vertical.
 Patterned Abrasion – pattern of weapon/ object
will be reproduced
 Non Patterned abrasion – pattern will not be
reproduced
1. Impact/imprint Abrasion:
The impacting force is vertical and it acts for
sufficiently long time to crush the epidermis resulting in
pressure type of abrasion and the imprint of impacting
object will be produced.
Usually seen in hanging where the pattern of ligature
material will be reproduced.
2. Contact Abrasion:
If a weapon with a pattern strikes at right angle to
body or if the body falls upon a patterned rough hard
surface, the abrasion will usually follow the pattern of the
object.
Classical example of this is seen in road traffic accident
when tyre of a car passes over body, it squeezes the skin
through the grooves of rubber thread leaving the pattern of
tyre marks.
Age of abrasion - helps to estimate time since injury
 Fresh – recent – bright red with no scab formation
 12 – 24 hrs – red in colour, moist scab
 2- 3 days – reddish brown dry scab
 4 – 7 days – dark brown scab
 8 – 14 days – scab fallen off – non pigmented
 14 – 28 days – partially pigmented – fully pigmented
Ante-mortem Abrasions:
 Reddish brown colour.
 Margins are blurred due to vital reactions.
Post-mortem Abrasions:
 Yellowish in colour.
 Translucent area.
 Margins are sharply defined.
 Absence of vital reactions.
Artifacts in Abrasion:

1. Bites by ants and insects
 Postmortem bites
 Moist & exposed areas
2. Excoriation of skin by excreta
 Seen in infants
 After death napkin area becomes dry, depressed and
parchment-like
Medico-Legal importance of Abrasion:
 Site of impact and possibility of internal injury.
 Identification of weapon causing the injury.
 Direction of injury.
 Time of injury.
Contusion/Bruise:
Contusion is an infiltration of extravasated blood
into the subcutaneous tissue resulting from rupture of
vessels by the application of blunt force.
The internal organs underneath the area of impact may
also show extravasation of blood.
In all such cases the integrity of skin and underlying
organs is not lost except in few cases where the skin is
abraded and called by the term ‘abraded contusion’.
Factors modifying the appearance of contusion:
1. Site of injury:
Flexible areas such as abdomen, buttock will bruise less
with a given blunt force impact than areas with
underlying bony prominence like head, shin etc.
2. Vascularity of area:
Prominence of a bruise varies according to the amount
of blood extravasated, hence areas like face, genitalia,
scrotum with rich vascularity will bruise more than
other areas.
3. Depth of bruise:
Delayed bruise
Contusion present in deeper planes of tissue will
appear after a long time from the time of impact and
hence called as ‘Delayed bruise’ or ‘Come out Bruise’
Ectopic Bruise
At times extravasated blood from damage tissues may
track along the muscular planes with least appearance
and appear at places other than the original site of
impact and they are called as ‘Ectopic Bruise’
Patterned bruise:
A patterned bruise is one in which the size and shape
of bruise will resemble a part of whole of the object
causing it.
 A blow with solid object like hammer will
produce a round contusion.
 A blow with a rod or a stick will produce two
parallel lines of contusion with area spared in
between – Railway Line/ Tram Line Contusion.
Colour change in bruise:
 Fresh – few hours - red in colour – extravasation of
blood
 One day – blue – RBC lysis – haemoglobin
accumulation

 2-5 days – brownish – degradation of haemoglobin -
hemosiderin
 6-9 days – greenish – haemotoidin
 10 – 12 days – yellowish – bilirubin
 More than 2 weeks – normal skin colour
Self-inflicted contusion/ Artificial bruise:
 Artificial bruise is a deliberately induced injury by a
person on himself to substantiate false allegation of
assault against another person.
 It can be inflicted by applying irritant substances like
juices of Marking nut, calotropis.
 It is usually seen in exposed and accessible parts of the
body.
 The artificial bruises are irregular in shape, dark brown
in colour, covered with small vesicles and surrounding
area shows sign of inflammation.
 The vesicles might be present also on the tips of fingers
used for applying the irritant juice.
 The vesicles contain acrid serum and it induces itching
in the surrounding area.
Contusion vs post-mortem lividity
Contusion Pm lividity
Cause Rupture of vessels and
extravasation of blood
Engorgement of vessels
due to pooling of blood
Site Anywhere Dependent parts
Surface Elevated Not elevated
Colour Changes with time Normally reddish purple
Incision Extravasated blood in
tissues – not washed off
Blood oozes out of cut
vessels – can be washed
off
Histology Signs of inflammation No signs of inflammation
Medico-Legal importance:
1. Identification of the object/ weapon.
2. Degree of violence.
3. Time of injury.
Laceration wounds/Injuries:
These are the wounds caused by the blunt force
resulting in tearing of the skin and the underlying tissues,
with a minimal bleeding.
Features of the lacerated wounds:
 Edges are ragged, irregular and contused.
 Deep tissues are crushed; Hair bulbs are crushed.
 Less bleeding due to crushing of underneath vessels.
 Presence of foreign materials.
 Shape-Irregular.
 Size-May or may not correspond to the weapon.
 Healing-Process delayed due to gross damage and
infection and produces permanent scar.
Types of laceration:
1. Split laceration:

 Split laceration are caused by crushing of skin
and underlying tissues between two hard
objects.
 Seen in cases of blow to tissues overlying bones -
scalp laceration occurs due to tissue being
crushed between skull and impacting hard
object.
 It simulates the incised wound as the margins
grossly look like cleanly cut but on magnification
shows irregular edges. So it is also called as
‘Incised Like Looking Laceration’
2. Stretch laceration:
 Due to over stretching of skin and tissues which
gives away.
 Laceration seen overlying bony fractures, where
the fractured ends of bones stretches the skin
overlying it.
3. Avulsion laceration:
 An avulsion may be seen when force is applied at
an acute angle to surface of the body sufficient
enough to detach the skin from underlying
tissues by its shearing and grinding force.
 Commonly seen in run over by vehicles, where
the wheel passing over the limb may produce a
separation of skin from underlying tissues.
(avulsion)
4. Tear laceration:
 Due to impact with irregular or blunt pointed end
of a weapon or an object on the surface of the
body.
 Stabbing with blunt pointed weapon causes tear
laceration.
5. Cut laceration:
 This type of lacerated wound is produce by “not
so sharp” edge of heavy weapon.
 Seen in chop wounds.
 Abrasions or contusions are seen on the margins.
Medico-Legal importance:
 Homicidal-occurs in any part of the body. produced by
blows with hard and blunt weapon.
 Suicidal-Very rare.
 Accidental-Road traffic accidents, accidental fall from
height.
 Foreign bodies-Mud, gravel, oil etc. helps in finding the
location.
Incised wounds:
Its produced by sharp cutting instruments-knife, razor,
blade, swords, chopper, axe etc.
Features:
 Edges are regular, clean cut.
 Except in neck and scrotum-margins irregular-
laceration like looking incision

 Spindle shaped wound, maximum widening in the
central part.
 Length is greater than the breadth.
 Gaping is greater if underlying muscles are divided
across or cut obliquely.
 Hemorrhage is excessive due to the clean division of
blood vessels.
 By nature of the incised wound, weapon used can be
identified.
 Light sharp cutting weapons-razor blades, knife
produces incised wounds by striking, drawing or by
sawing.
Drawing cuts-
Deeper at start, gradually become shallow and at the
end only skin is cut “Tailing of the wound” – indicates the
direction of stroke.
Sawing cuts –
Multiple at the beginning and only one deep cut
wound called “Tentative or Hesitation cuts”- usually seen
in suicidal cases.
Bevelling cuts-
When weapon is used oblique or tangential way over
the body, it raises a flap from underlying tissues.
STAB WOUNDPUNCTURED WOUND:
 These are the deep wounds produced by the pointed
end of a weapon or an object, entering the body.
 These injuries generally caused by ‘weapons with
pointed ends -knives, dagger, bayonet, arrow, pick-axe,
broken glass pieces.
 The depth of the wound will be more than length and
breadth of the wound.
 Depth is the greatest dimension of a stab wound
produced by the length of the weapon introduced.
 The length and breadth of wound corresponds to the
breadth and thickness of the weapon respectively.
 A stab wound caused by a sharp pointed weapon will
have clean cut edges,
caused by a blunt pointed weapon will
have irregular edges.
 When the edges of the weapon are sharp, the wound
produced is an ‘Incised penetrating wound’.
 When the weapon edge is blunt, it produces a
‘Lacerated penetrating wound’.
 Shape of the wound in case of stab wound depends on
the shape of the weapon and its edges.
 In case of weapon with one edge sharp we will have
acute end corresponding to the sharp end and obtuse
end corresponding to blunt edge of weapon.
 In case of weapon with both edge sharp, we will have
both ends of wound to be acute

Weapon with single sharp edge producing one acute
angle end and one obtuse angle end.
 Weapon with double sharp edges producing
wounds with both ends acute angled.
 Hilt marks are common when the weapon is pushed till
the handle.
 When a stab wound enters into a body cavity -
thoracic, abdominal, joint cavities it is called as
‘penetrating wound’.
 When the wound pierces the body through and
through and comes out it is known as ‘perforating
wound’.
Chop wounds:
 Heavy sharp cutting weapons-like swords, axes, choppers
etc. chop wounds are greater and severe. Usually
homicidal in nature.
 Injuries caused by these weapons show signs of bruising
over the edges and extensive damage to deeper structures
and organs.
Medico-Legal importance
MANNER
 Homicidal-Any part of the body, commonly on the neck,
head and trunk, also be found on the inner side of
forearm or hand of victim while defending or
protecting. ‘Defense Wounds’.
 Suicidal-Found in the accessible parts by light weapons
on the throat (cut throat wounds). Tail end of the
wound indicates which hand has been used.
 Accidental-Any part of the body hands, fingers during
the handling of knife, razor blades etc.
Identifying weapon
 Incised wound indicates use of sharp cutting weapons.
 Beveled cuts and chop wounds suggest use of heavy or
moderately heavy sharp cutting weapons.
Manner of use of weapon
 Deep chop wounds and beveling suggests striking with
the weapon.
 Tailing cuts indicate drawing of the weapon.
 Multiple superimposed or overlapping injuries are
indicated by saw like movement of the weapon.
Direction of application of force
 From the tailing and beveling, the direction of
application of force can be known.
 The relative position of the victim and the assailant can
also be known, by the direction of application of force
Age of the wound or time since injury
 In case of dead bodies-histological examination of tissue
from the margin of the wound, gives the clue that the
survival of time after injury.
 When fresh- Bleeding is still present or fresh soft clot is
adhered, margins are red, swollen and tender.
 By 12 hrs- Blood clot and lymph dry up, margins are red
and swollen. Histologically there is infiltration of
leucocytes.
 By 24 hrs- Proliferation of connective tissue cells and
vascular endothelium for neo-vascularization.
 By 36 hrs- Fibroblastic infiltration and capillary network
formation starts.

 By 48 hrs- Capillary network is completed. Fibroblasts
run across the new vessels.
 By 3-5days- Vessels are obliterated and thickened,
wound heals and scar formation starts and advances.
 By 6th
day- Scar formation is completed. Scab over the
wound falls off.
 After weeks to months, soft, tender, reddish scar
becomes tender less, whitish and firm.
FRACTURE
Fracture of a bone is defined as disintegration or breakage
of bone due to blunt/ sharp force acting either directly or
indirectly.
Direct Fractures
1. Focal fractures
 Small force applied to a small area. Injury to overlying
soft tissue is minimal.
Eg-forearm and leg, while defending blows during an
attack.
2. Crush fractures
 It results from application of a large force over a large area
and is typically fragmented.
 Injury to the surrounding soft tissue is usually extensive.
 If two bones lie adjacent to each other, both are involved.
Eg- fracture of tibia and fibula in RTA.
3. Penetrating fracture
 It results from applications of a large force over a small
area.
Eg- Bullet injury to a bone.
Indirect Fractures
1. Traction Fractures
2. It results when a bone is pulled apart by traction.
i. Eg- Transverse patellar fracture due to violent
contraction of quadriceps.
3. Angular fraction
It occurs due to bending of bone. The concave surface of
the bend is compressed, while the convex surface is put under
traction resulting in breakage.
4. Rotational fracture
Fracture in spiral, when the bone is twisted in opposite
direction.
5. Vertical compression fracture
In this type, when a proximal part of bone is compressed
against distal part, an oblique fracture with driving of
proximal part into distal part results.
Repair and healing of the fracture
Healing of the fracture depends on the age and nutritional status
of a person.
1. Haemorrhage phase.
2. Proliferation phase.
3. Callus phase.
4. Consolidation phase.
5. Remodelling phase.
 In the Hemorrhagic phase, bleeding will be at the site of
fracture.
 In the Proliferation phase, a collar is formed around the
fractured ends by proliferation of cells from periosteum
and endosteum.

 In the Callus phase, cellular elements give rise to
osteoblasts and chondroblasts which produce a matrix of
collagen and polysaccharide, impregnated with calcium.
 In the Consolidation phase the callus is transformed into
mature bone by 4-6weeks in children and in adults by 12-
14weeks.
 In the final, the Remodeling phase, matured bone will take
place.
Medico-Legal Importance:
1. Fracture of a bone constitutes grievous injury according
to law.
2. The type of fracture can give the clue of causative force,
whether direct, indirect, rotational or angular etc.
3. Age of fracture/ injury can be found out from healing
stage
4. The site of fracture may help to indicate the cause of
death.
Eg- fracture of hyoid bone suggestive of throttling.

7.FORENSIC BALLISTICS
Forensic ballistics
 Forensic ballistics is the science dealing with the
investigation of firearms, ammunition and the problems
arising from their use.
Firearms
 A firearm is any instrument which discharges a missile
by the expansive force of the gases produced by burning
of an explosive substance.
Proximal ballistics:
 Study of firearms and projectile
Internal ballistics:
 Study of motion of a projectile after its ejected until it
hits the target
Terminal ballistics:
 Study of injuries produced by firearms
Fire arm
 A firearm consists of a metal barrel in the form of
hollow cylinder of varying length which is closed at the
back end (breech end) and an open front end (muzzle
end).
 A chamber at the breech end to accommodate the
cartridge.
 A taper that connects the chamber to barrel.
Types
According to barrel
1. Rifled
The barrel is grooved spirally so that it gives a spinning
movement to bullet.
2. Smooth bore
The barrel is not grooved and it is smooth.
Ammunition
 A round of ammunition. Generally, refers to a single,
live, unfired, cartridge comprising the missile, cartridge
case, propellant and some form of primer.
Primer
 Highly sensitive explosive chemical which, when struck
by the firing pin or hammer of a weapon, will explode
with great violence, causing a flame to ignite the
propellant
 Mercury fulminate/ lead azide
 Potassium chlorate
 Antimony sulphide
Propellant
Present in the body of cartridge
Three types
1. Black powder
2. Semi smokeless powder
3. Smokeless powder
Black powder
Chinese traditional gun powder
 75% potassium nitrate (salt peter)

 15%charcoal, and
 10%sulfur,
Large quantity of bluish-grey smoke and a characteristic
sulfurous residue
Smokeless powder
 Smokeless powders compounded from
 Nitrocellulose – single base
 Nitrocellulose + Nitro-glycerine – double base
 They generate some smoke but not to the extent of black
powder
 Power generated is much higher than tradition black gun
powder.
Semi Smokeless powders compounded
20% smokeless powder + 80% black powder
BULLET
 A bullet is a projectile propelled by a firearm, sling, or
air gun.
 A bullet does not contain explosives, but damages the
intended target by its impact or penetration
Shotgun cartridge:
THE PROJECTILES
Small round lead balls or lead-antimony alloy for added
hardness.
 Pellets used in shotgun cartridges
 Lead with a small amount of antimony to increase their
hardness
 Soft steel, usually with a copper coating;
 Bismuth, a heavy metal often alloyed with iron;
 Tungsten, a very heavy metal often alloyed with iron
THE BRASS HEAD
 Forms the base of the shot shell,
 Contains the primer, and is in direct continuity with the
cartridge case.
 The base has a rim to allow extraction of the spent shell
after discharge.
THE CARTRIDGE CASE
 Contains the gun powder, wadding, piston, and
projectiles.
PISTON
 To contain the projectiles.
 The function of the piston is:
 to contain the projectiles in a tight cluster until the
instant of muzzle exit
THE WADDING
 Discs of cardboard (commonly called cards) or felt
 To separate the propellant from the projectiles and
 To secure the projectiles at the apex of cylinder.

Classification of guns:
Hand guns:
 Single shot and double barrel pistols
 Revolvers
 Semiautomatic pistols
 Automatic and machine
pistols
 Air pistols
Long arms
Rifles
 Single shot
 Magazine repeaters
1) Lever action
2) Slide or pump action
3) Single shot bolt action
4) Semiautomatic
5) Automatic
Caliber of rifled firearm:
 It is the size of the barrel
of a rifled firearm.
 It is the distance between two vertically opposite lands
in the barrel of a rifled firearm.
e.g 9mm caliber means the distance between two
vertically opposite land inside barrel of this rifled
firearm is 9 millimeter
Gauge of a smoothbore Firearm (Shotgun):
 It is the size of the barrel of a smoothbore firearm
 It is the number of lead balls of equal diameter that
exactly fits into the barrel of shot gun that can be made
from one pound of lead.
e.g 16 gauge shot gun means 20 lead balls, all of equal
diameter of size that exactly fits into this shot gun made
from one pound of lead
Choking of shotgun:
• A choke is a tapered constriction of a shotgun barrels
bore at the muzzle end.
• Purpose is to shape the spread of the shot in order to
gain better range and accuracy
Types of Bullets:
1. Ricochet bullet:
 A type of bullet which gets bounced back or deflected
by striking an intermediary hard object before
striking the target.
2. Tandom bullet or piggy tail bullet:
 Sometime one bullet may get logged inside the barrel
without getting out, so on second firing, the second
bullet along with first bullet comes out
3. Dum Dum bullet:
 The tip of bullet is hollow with grooves made up of
lead, so that when it strikes a target it expands and
produce larger wound.
Smooth bore
firearms:
 Single barreled
 Double barreled
 Magazine repeaters
1) Lever action
2) Slide or pump
action
3) Bolt action
4) Self-loading or
semiautomatic shot
guns

4. Frangible bullet:
 Entire bullet is made up of iron and easily frangible
metals, so that on hitting the target its breaks into
multiple fragments and produce greater damage
5. Incendiary bullets:
 Contains white phosphorous/ barium nitrate and
powdered aluminum and magnesium at the tip of it
 ignited upon firing
6. Tumbling bullets:
 When the bullet in motion rotates end to end after
firing in its projectile.
7. Souvenir bullet:
 when the bullet remains existing within the body
encapsulated with dense fibrous tissue.
8. Tracer bullets,
 Leaving a trail of blue smoke
 Rear portion is filled with barium nitrate/ powdered
strontium nitrate and magnesium
Components of a Shot responsible for damage
 Bullet – spinning moment - Abrasion collar
 Flame & heat – Singeing of hair, burning of skin
 Smoke - Blackening
 Unburnt gun powder - Tattooing
 Grease from the barrel - Grease collar
RIFLED FIRE ARM
ENTRY WOUND –
SINGLE HOLE:
Inverted margins.
SHAPE:
 Depending upon the angle of firearm with the body
 -Circular,
 Oval/ Elliptical,
 An elongated furrow.
SIZE :
 Proportionate to the diameter of the bullet
 Small - skin elasticity
 Large - explosive blast effect of gases so either
1. Contact shot
 Entry wound of variable shape with collar of abrasion
 Burning, blackening, tattooing present in the track or
interior of wound
 Pinkish discoloration due to CoHb.
 Muzzle imprint on close examination.
 Margins may be inverted or everted
2. Close shot (within range of flame)
 Barrel is held close to skin in the range of flame &
smoke -7.5 cm in revolvers / pistol - 15 cm in rifles
 Circular defect, Inverted margins.
 Burning, singing present. (Flame)
 Blackening present. (smoke)
 Tattooing present. (un burnt powder)
 Collar of abrasion, grease present
3. Near shot (within range of un burnt powder)
 Barrel is held in the range of out of flame but within
unburnt powder -60 cm in revovlers/pistol, 75- 90 cm
in rifles
 Burning, scorching absent. (Flame)
 Blackening absent. (smoke)
4. Distant Shot (out of range of un burnt powder)

 Barrel is held in the range of out of unburnt powder
>60 cm in revolvers/pistol, >90 cm in rifles
 Tattooing absent. (un burnt powder)
SMOOTH BORE FIRE ARM - SHOT GUN
1. Contact shot
 Entry wound usually large due to blast effect
 Burning, blackening, tattooing present in the track or
interior of wound
 Pinkish discoloration due to CoHb.
 Muzzle imprint on close examination.
2. Close shot (within range of flame)
 Barrel is held close to skin in the range of flame &
smoke –upto 30 cm
 Burning, scorching present. (Flame)
 Blackening present. (smoke)
 Pellets travel as single mass
 Surrounded by contusions by card disc,
3. Near shot (within range of un burnt powder)
 Barrel is held in the range of out of flame but within
range of unburnt powder 60 to 90 cm
 Up to 45 cm – single entry wound
 45 cm to 1 meter – single wound with scalloped
margins – rat hole entry wound.
4. Distant Shot (out of range of un burnt powder)
 Barrel is held in the range of out of unburnt powder
>1 meter
 Satellite entry wound: multiple small entry wound
surrounding the central entry wound will be there
from 1 meter to 2 meters
 Central entry wound size decreases proportionately >
2 meters
 >5 meters no central entry wound
 Tattooing absent. (un burnt powder)
Medicolegal importance
 Bullets
 Size
 Weight

 Number
 Kind of metal
 Striations in it – identification of weapon.
Test firing and comparing
 If weapon and bullet recovered from scene of crime
 Test fire it and collect the bullet.
 Compare the test fired bullet with the bullet
recovered after postmortem from the decease.
 Study various marks and compare with comparison
microscope
Striations
 As the bullet travels through the barrel, the grooves
guide the bullet and cause it to spin.
 Striations, or fine lines, in the gun barrel make the
same striations on the bullet. These striations are
unique to the firearm.
Identifying Marks from the Firing Pin
 Metal-to-metal contact between the bullet case and
the firing pin leaves an impression on the case. This
impression is in the shape of the firing pin.
 A shotgun has a smooth barrel so the projectile is
not marked with any type of striation.
 However, the shotgun cartridge may have the same
markings as a bullet case.
Gunshot Residues GSR:
 When a firearm is discharged, unburned and partially
burned particles of gunpowder in addition to smoke
are propelled out of the barrel along with the bullet
towards the target.
 The GSR is most likely concentrated on the thumb
web and the back of the firing hand.
 The GSR stays on the hands for approximately 2
hours and is easily removed by washing or wiping the
hands.
 In a suicide, the hands will be bagged and tested for
GSR at the Medical Examiner’s office.
 The Dermal Nitrate Test, developed in 1933, was
used for many years. However, many false positives
with cigarette ash, urine and cosmetics.
 During the test, the suspects hands were covered in
wax. After the wax hardened it was removed and
chemically tested.
 Barium, copper, lead and Antimony are both
components in GSR. Several techniques are used to
test for these elements.
 First, the investigator will remove the GSR particles
with tape or swabs.
 Next, the particles may be examined with a Scanning
Electron Microscope, Neutron Activation Analysis or
Flameless Atomic Absorption Spectrophotometry
Manner of death

8.THERMAL BURNS
• Thermal burns are injuries caused by exposure of living tissue
to high temperatures that will cause damage to the cells.
• The extent of the damage caused is a function of the length of
time of exposure as well as of the temperature to which the
tissues are exposed.
• The minimum temperature required to cause cell damage
• 44°C if exposed for several hours,
• Over 50°C or so, damage occurs more rapidly,
• At 60°C tissue damage occurs in 3 seconds.
The heat source may be dry or wet;
• where the heat is dry, the resultant injury is called a
‘burn’,
• whereas with moist heat from hot water, steam and
other hot liquids it is known as ‘scalds’.
Classification of thermal burns according to sources of heat
1. Flame burns
• In flame burns, there is actual contact of body and
flame, with scorching of the skin progressing to
charring.
• Flame burns may or may not produce vesication but
singeing of hairs and blackening of skin is always
present.
• Hair singed by flame burns become twisted and
curled, breaks off or is totally destroyed.
2. Flash burns
• Flash burns are a variant of flame burns.
• They are caused by the initial ignition flash fires that
result from the sudden ignition or explosion of gases,
petrochemicals or fine particulate material.
• Typically, the initial flash is of short duration, a few
seconds at most and because the thermal conductivity
of the skin is low, the burn is superficial.
• All exposed surfaces are burned uniformly.
• Flash burns usually result in partial-thickness burns
and singed hair.
• If the victim’s clothing is ignited, a combination of
flash and flame burns occurs.
• Flash burns from methane explosion. Hair singed.
3. Contact burns
• Contact burns involve physical contact between the
body and a hot object.
• A heated body when applied to the body for a short
period causes a blister or reddening corresponding to
the size and shape.
• For a longer duration causes, trans-epidermal
necrosis.
• The hair may be singed or distorted.
4. Radiant heat burns
• They are caused by heat waves a type of
electromagnetic wave.
• There is no contact between body and flame, or
contact with a hot surface.
• Initially, the skin appears erythematous and blistered,
with areas of skin slippage.
• With prolonged exposure to low heat, the skin will
become light brown and leathery

• Radiant heat burns with erythema, blistering of skin
and skin slippage
Classification of thermal burns according severity of burn
injuries:
1. Dupuytrynes
I degree – erythema with transient swelling
II degree –vesication with blister formation
III degree – partial destruction of dermis
IV degree – complete destruction of dermis
V degree – involvement of subcutaneous tissues and also
the muscles
VI degree involvement of bones
2. Hebras classification
1st
degree - Involves only epidermis
2nd
degree - Involves both epidermis and dermis
3rd
degree - Involves subcutaneous tissues, muscles and
bones.
3. Wilsons Classification
Epidermal - Involves only epidermis
Dermo epidermal - Involves both epidermis and dermis
Deep - Extend beyond dermis.
4. Evans classification
Superficial burn - involves only epidermis
Partial thickness - involves both dermis and epidermis
Full thickness - involvement beyond dermis
5. Muir and Sutherlands classification
Superficial partial thickness burn
Deep partial thickness burn
Full thickness burn
6. Modern day classification
I. First degree (superficial)
o Redness without blister
o Involving only epidermis
o painful
II. Second degree
a. Superficial partial thickness
o Redness with blisters
o Extending into superficial papillary dermis
o Very painful
b. Deep partial thickness
o Yellow or white burns
o Extending into deep reticular dermis
o Pressure discomfort with no pain.
III. Third degree
o Full thickness – white/ brown
o Extending into entire thickness of skin.
o Painless
IV. Fourth degree
o Black, charred with Escher formation
o Extending into entire skin, subcutaneous fat, muscles
and bone.
o Painless
Classification of burn injuries according to involvement of
body surface area:
Wallace rule of nine divides body surface into following regions
o Head, neck and face - 9 %
o Front of thorax - 9 %
o Back of thorax - 9 %
o Right upper limb - 9 %
o Left upper limb - 9 %
o Front of abdomen - 9 %
o Back of abdomen - 9 %
o Front of right lower limb - 9 %
o Back of left lower limb - 9 %

o Genitals – 1%
Causes of death in victim of burn injuries:
1. Primary (neurogenic) shock due to pain
2. Secondary shock due to fluid loss (in 48 hrs)
3. Smoke inhalation – CO, Cyanide, free radicals.
4. Biochemical disturbances secondary to the fluid loss and
destruction of tissues.
5. Acute renal failure usually occurs on third or fourth day.
6. Sepsis occurring after four to five days.
7. Gastrointestinal disturbances, as peptic ulceration, dilation
of stomach, hemorrhage into intestines.
8. Edema of glottis and pulmonary edema due to inhalation
of smoke containing CO.
9. Pyaemia, gangrene, tetanus etc
10. Pulmonary embolism from thrombosis of veins of legs
11. Death due to malignant transformation of a burn scar
(Marjolin’s ulcer)
Postmortem appearance in a deceased died due to burn
injuries:
External
1. Clothes
 Cotton fabrics burns faster.
 Nylon, polyester and wool produce less severe burns.
 Close fitting garments are safer.
 Portions of body under tight fitting are comparatively
unaffected, like belts, shoes, brassier or buttoned collar.
 All clothes should be sent for examination of flammable
substances
2. Hair changes
 Hairs are singed, twisted, charred, broken off or completely
destroyed.
 In lesser degree of burns, bulbous enlarged of hair ends
present.
 The hairs present in armpits and skin folds are sometimes
spared from singeing.
 The color of light hair changes on exposure to heat.
o at 1200
C gray to brassy blond
o 2000
C for 10 – 15 minutes brown hair to slight reddish.
 The black hair will show no color changes on exposure to
heat.
 Any unburnt or partially singed hair should be sent for
examination for flammable substances.
External changes:
 The face may be swollen and distorted
 Tongue protrudes and burnt due to contraction of muscles
of neck and face.
 Froth may be present at mouth and nose due pulmonary
edema caused by irritation of air passages.
1. Heat ruptures
 In severe burning, skin and underling tissues contracts and
bursts to form heat ruptures.
 Usually seen in extensor aspects of limbs and joints.
 Several centimeters in length and resembles lacerations or
incised wounds,
 Differentiated by
o Absence of bleeding as heat coagulates the blood in the
vessels.
o Intact vessels and nerves at the floor
o Irregular margins
o Absence of vital reactions in the margins.
 Can happen before and after death of individual.
2. Pugilistic attitude

 The characteristic posture of a body which has been
exposed to high heat.
o Legs – flexed at hips and knees
o Arms – flexed at elbows and wrists, held out in front of
body
o Head – slightly extended
o Fingers – hooked like claws.
o Trunk – Opisthotonus due to contraction of para spinal
muscles.
 The attitude is similar to boxers defending position,
pugilism(sport of fighting with fist) and so the name.
 This stiffening is due to coagulation of proteins of the
muscles and dehydration.
 The flexor muscles being bulkier than extensors their
contraction causes this attitude.
 It occurs in both alive and dead at the time of burning.
Internal changes
1. Heat hematoma
 Whenever head is exposed to intense heat, there will be
collection of clotted blood in extradural space of1.5 mm to
15 mm thickness
 Soft, friable clot of brown/ pink color due to presence of
carboxy hemoglobin
 On cut section of clot, Honeycomb appearance is present
due to bubbles of stream produced by heat.
 Parieto-temporal region is the most common site.
 Mechanism of development is due to contraction of
meninges and expansion of blood in venous sinuses
expulses the blood in extradural space.
 Resembles extradural hemorrhage but with no signs of
external injuries.
 Charring of surrounding outer table of vault.
2. Thermal fractures of skull
 Two mechanism of causation
o Increase in intracranial pressure bursting the non-united
sutures and producing widely separated bony margins.
o Due to rapid drying of the bone causing contracture of the
outer table.
 Usually seen on either sides of template region.
 Usually stellate shaped
 May crosses the suture line.
 Fractures of long bones are also seen in cases of intense
heat
 Due to excessive shrinkage of muscles attached to bones.
 Completely burnt bones will be greyish white in colour.
3. Inhalational injuries

 Carbon monoxide levels will be more than 10% and can go
up to 70 to 80 %
 Children and old people die at 30 to 40 %
 Aspirated blackish coal particles are seen in nose, mouth,
larynx, trachea, bronchi, esophagus and stomach.
 When mouth is open, passive percolation of soot particles
may present up to pharynx but not beyond vocal cords.
 Inhalational injuries can occur due to other poisonous gases
like cyanides and oxides of nitrogen
 Presence of carbon particles and an elevated CO level are
absolute proof of patient being alive at the time of burns.
 If flame or super-heated air is inhaled, burns are seen
interior of mouth, nasal passages, larynx with vocal cord
epithelium destruction, edema of larynx and lungs are seen.
4. Brain and Meninges
 Usually shrunken.
 Firm in consistency.
 Yellow to light brown in color.
 Dura matter becomes leathery.
 Dura matter may split with brain matter oozing out forming
frothy paste.
5. Pleura and Lungs
 Pleura are congested and inflamed.
 Lungs are usually congested and edematous.
 Heavy, airless and consolidated.
 Blood vessels of lungs may contain a small amount of fat
due to physio chemical alteration of already fat present.
6. Heart and Pericardium
 Petechial hemorrhages present in pleura, pericardium and
endocardium.
 Heart is usually filled with clotted blood.
 Interstitial edema and fragmentation of myocardial fibers
are also seen.
7. Gastro intestinal tract
 Inflammation and ulceration of peyers patches and glands
of the intestines.
 Curlings ulcer
o Seen in less than 10% cases
o Usually seen after 10 days of survival
o Sharp punched out lesions in duodenum
o May be superficial or deep
 Gastric ulcers may occur within a day.
 May erode vessels leading to fatal hemorrhage
8. Spleen
 Enlarged and softened
9. Liver
 Enlarged and congested
 May develop jaundice
10. Kidneys
 Enlarged with capillary thrombosis and infarction
11. Adrenals
 Enlarged and congested
Time of death in burns cases
The features from which time since death were assessed are
altered in a case of complete burns.
 Rigor mortis cannot be assessed as most of muscles tissues
are destroyed.
 Heat rigors may be present in the muscles.
 Postmortem hypostasis cannot be assessed in completely
burnt bodies, as skin over the body are usually charred and
destroyed.
 Body temperature will also be altered in complete burns.

Thus its always difficult to assess the time since death in burns
cases.
Establishment of identity
 Weight and height are unreliable in complete burns
Due to drying of skin,
Skeletal fractures
Pulverisation of intervertebral discs
 Moles, scars and tattoo marks are usually destroyed
 Dental charts should be prepared and used.
 Postmortem x rays can be compared with previous x rays of
suspected individual.
 DNA typing and identification will be useful
 Sex can be identified by presence of uterus or prostate,
which resist burning to marked degree.
 Personal belongings like key chains, watch, buttons, belt
buckle and cuff links are also useful
Antemortem burns
Line of redness
 5 to 20 mm in width.
 Surrounds the burnt area.
 Involves whole thickness of skin
 Permanent and persist after death
 Absent when whole body is burnt.
Antemortem Blisters:
 Raised dome with gas or fluid
 Contains serous fluid with proteins
 Base and periphery shows red and inflamed areas.
 Surrounding areas show increase in enzymes like acid
mucopolysaccarides.
Postmortem Blisters:
 Dry, hard and yellow
 Contains air and thin Clear fluid
 Base is not inflamed.
 Peripheral zone doesn’t shows increase in enzymes.
Circumstances of burns
Accident:
 Women’s clothes may caught in fire while cooking.
 Injuries are concentrated in front of thighs, chest, abdomen
and face.
 Hands also shows injuries as they will try to douse the fire.
 Feet and ankles are spared.
 While lying on a flat surface, the skin resting is spared
Suicidal burns:
 Extensive burns present all over the body.
 Only the skin folds such as axillae, perineum and soles are
spared.
 Sometimes person use to keep clothes in mouth to
suppress the cries.
 Inflammable substances are usually present in high
amounts in head.
Homicidal burns:
When inflammable substances are thrown and lighted, then the
burns are found more on.
 Sides of neck.
 Sides of trunk.
 Between the thighs.
 Attempts may be made to burn the body after the homicide
to conceal the crime.
So in all cases of burns, during postmortem the presence of any
other fatal injuries should be identified.
Sometimes chemicals, irritating substance, hot boiling liquids are
thrown over the victims with the criminal intension.

Forensic Medicine Notes 157 Pages-1.pdf

Forensic Medicine Notes 157 Pages-1.pdf

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