Soham Bhattacharya's document discusses hair evidence in forensic investigations. It provides background on the history of using hair analysis dating back to the late 1800s. Hair is considered class evidence that cannot identify a specific individual unless the follicle is present for DNA analysis. Hair can persist for long periods on surfaces and clothes due to its tough outer coating and resist decomposition. The recovery of hair evidence can occur at the crime scene or in laboratories.

1. NAME- SOHAM BHATTACHARYA
BRANCH- B.SC FORENSIC SCIENCE
SUBJECT- FORENSIC BIOLOGY

2. TOPIC- PERSISTENCE AND RECOVERY OF
HAIR EVIDENCE
CONTENT
•INTRODUCTION
•ABOUT HAIR EVIDENCE
•HAIR PERSISTENCE
•RECOVERY OF HAIR EVIDENCE

3. HISTORY OF HAIR EVIDENCE
• INVESTIGATORS RECOGNIZED THE IMPORTANCE OF ANALYSIS OF HAIR AS TRACE
EVIDENCE IN CRIMINAL INVESTIGATIONS INTHE LATE 1800S
• THE USE OF THE COMPARISON MICROSCOPE TO PERFORM SIDE BY SIDE ANALYSIS OF
HAIRS COLLECTED FROM A CRIME SCENE AND HAIRS FROM A SUSPECTS OR VICTIM FIRST
OCCURRED IN 1934 BY DR. SYDNEY SMITH.

4. ABOUT HAIR EVIDENCE
oHAIR IS CONSIDERED AS CLASS EVIDENCE. ALONE IT CANNOT BE USED TO IDENTIFY A
SPECIFIC INDIVIDUAL.
oIF FOLLICLE CELLS ARE ATTACHED TO THE HAIR, THEN IT CAN BE INDIVIDUALIZED
THROUGH DNA!
oHAIR CAN EASILY BE LEFT BEHIND AT A CRIME SCENE. IF CAN ALSO ADHERE TO CLOTHES,
CARPETS, AND MANY OTHER SURFACES AND BE TRANSFERRED TO OTHER LOCATIONS.
THIS IS SECONDARYTRANSFER.
oBECAUSEOF ITSTOUGH OUTERCOATING, HAIR DOES NOT EASILY DECOMPOSE.
oCHEMICAL TESTS CAN PROVIDE A HISTORY OF THE USE OF DRUGS AND OTHER TOXINS,
INDICATE THE PRESENCE OF HEAVY METALS, AND PROVIDE AN ASSESSMENT OF
NUTRITIONAL DEFICIENCIES.

5. WHAT ARE PERSISTENCE
EVIDENCE
INA FORENSICCONTEXT,THEWORD ‘PERSISTENCE’ MEANSTHATTHE LENGTHOFTIME
TRACE EVIDENCE REMAINSONTHE SURFACETOWHICH ITWASTRANSFERRED FROMTHE
TIMEWHENTHE CONTACT ANDTRANSFERTOOK PLACE.

6. HAIR PERSISTENCE
SINCE IT IS RARE FOR SUSPECTS TO BE APPREHENDED IMMEDIATELY AFTER HAIR TRANSFER
IN A CRIME, THE CONCEPT OF HAIR PERSISTENCE ON CLOTHING MOVEMENT AND LOSS OF
HAIRS ON CLOTHING HAS BEEN FOUND TO BE INFLUENCED BY MANY VARIABLES AND IT
WAS CONCLUDED THAT ‘ IT WOULD BE QUITE UNJUSTIFIED TO ATTEMPT TO PREDICT
ACCURATELY THE NUMBER OF HAIRS LIKELY TO BE PRESENT IN A SPECIFIC CASE OR TO
ATTACH GREAT SIGNIFICANCE TO WHERE THESE HAIRS ARE FOUND’. ALTHOUGH MOST
HUMAN HAIRS ARE REMOVED FROM ITEMS DURING LAUNDERING, SOME CAN STILL BE
FOUND ON ITEMS AFTER LAUNDERING AND HAIR TRANSFERS CAN OCCUR DURING
LAUNDERING.

7. RECOVERY OF HAIR EVIDENCE
RECOVERY OF HAIR EVIDENCECAN OCCUR INTWO LOCATIONS
1. ATTHE CRIME SCENE
2. INTHE LABORATORIES