Crime scene personnel are typically the first to arrive and secure the scene, detaining any persons of interest. The crime scene unit then documents the scene in detail, collecting any physical evidence. The district attorney may be present to help determine if search warrants are needed. Medical examiners could determine preliminary cause of death. Forensic experts like entomologists may be called in if needed. Investigators interview witnesses and follow leads from evidence. Forensic science disciplines at state police crime labs include drug chemistry, trace chemistry, microscopy, biology/DNA, toxicology, latent prints, ballistics, toolmarks, and questioned documents to analyze evidence. Proper crime scene protocol is to note witnesses and victims, identify potential evidence, photograph

1. Vocabulary Crime Scene Personnel
__________ __________: Any physical location in which ____________ ______________ are typically the first
a crime has occurred or is suspected of having occurred. to arrive at a crime scene. They are responsible for
_______________ CRIME SCENE: The original location securing the scene and detaining persons of interest.
of a crime or accident. The _____ UNIT documents the crime scene in detail
_______________ CRIME SCENE: An alternate location and collects any physical evidence.
where additional evidence may be found. The DISTRICT ______________ is often present to
______________: Person thought to be capable of help determine if any search warrants are required to
committing a crime. proceed and obtains those warrants from a judge.
______________: Person associated with someone The MEDICAL _________________ may or may not
suspected of committing a crime. be present to determine a preliminary cause of death.
______________ : Statement of where a suspect was at ____________________ (entomologists, forensic
the time of a crime. scientists, etc.) may be called in if an expert is needed.
____________________ interview witnesses and
Types of Evidence consult with the CSI unit to investigate the crime by
following leads provided by witnesses and evidence.
_________________ evidence includes oral or written
statements and testimony by eyewitnesses.
Forensic Science disciplines at the
______________ evidence refers to any material items Investigating the Evidence Illinois State Police Crime Labs
that would be present at the crime scene, on the victims,
Drug Chemistry – Determines the presence of
or found in a suspect’s possession.
controlled substances and the identification of marijuana
_____________ evidence refers to evidence that is found
Trace Chemistry - Identification and comparison of
at a crime scene in small but measurable amounts.
materials from fires, explosions, paints, and glass.
Microscopy Lab – Microscopic identification and
How can evidence be used? comparison of evidence, such as hairs, fibers, woods,
May prove that a crime has been committed soils, building materials, insulation and other materials.
Establish key elements of a crime
Link a suspect with a crime scene or a victim Biology/DNA – Analysis of body fluids and dried stains
Establish the identity of a victim or suspect such as blood, semen, and saliva.
Corroborate verbal witness testimony Toxicology – Tests body fluids and tissues to determine
Exonerate the innocent. the presence of drugs and poisons.
Give detectives leads to work with in the case
Latent Prints - Identification and comparison of
fingerprints or other hidden impressions from sources
like feet, shoes, ears, lips or the tread on vehicle tires.
Crime Scene Protocol
______________ the first officer on the scene, Ballistics (Firearms) – Study of bullets and ammunition
witnesses, and victims to determine what happened. through the comparison of fired bullets, cartridges, guns,
and gunpowder patterns on people and objects.
______________ the crime scene to identify potential
evidence, the point of entry and point of exit, and getting Toolmarks – Examines marks left by tools on objects at
the general layout of the crime scene. a crime scene or on a victim, such as a hammer used to
break a door or a screwdriver used to pick a lock.
_________________ the crime scene by taking
photographs and making sketches of the crime scene area Questioned Documents - Examination of documents to
and the location of the evidence. compare handwriting, ink, paper, writing instruments,
printers, and other characteristics that would help to
____________ the crime scene by collecting evidence. identify its origin.
T. Trimpe 2009 http://sciencespot.net/

2. What evidence would you collect from this crime scene? Circle the evidence
you would collect and explain how you might use it in the investigation.
T. Trimpe 2
2009 http://sciencespot.net/