Name __________________________________
Period: _________________________________
09/11/09
Ms. Martin
The Organization of a Crime Laboratory
AIM: [What are the major departments of a full service crime lab? What do these
departments do?]
DO NOW:
FRIDAY FIVE MINUTE MYSTERY: MY PAL PATSY
How did Doctor Melville know who committed the murder?
NOTES:
 Forensic science is the application of SCIENCE to LAW

Crime labs vary from place to place because of LOCAL LAWS, available manpower &
DEMAND

Crime labs are mostly connected to LOCAL POLICE DEPARTMENTS. Others are
connected to the district attorney’s office, medical examiner, coroner, universities, or
government agencies (FBI).

The FEDERAL BUREAU OF INVESTIGATION (FBI) runs the main forensic laboratory
in the US. The FBI labs have a ton of resources including comparison standards for
paint samples, tire patterns, DNA, bullets, fibers, etc.
Full service crime labs have many units:
BASIC SERVICES
Applies principles and techniques of chemistry, physics, and
Physical Science Unit
geology to THE IDENTIFICATION and COMPARISON OF
crime scene evidence.
Identification of BLOOD STAINS and other body fluids,
Biology Unit
comparison of HAIRS and FIBERS identifying substances such
as wood and plants.
Firearm Unit
Examination of guns, bullets, cartridge cases, shotgun shells,
ammunition, gunshot residue
Document Examination Unit
HANDWRITING analysis. Examines potential forgeries,
analyzes ink, paper, burned documents
Uses specialized photographic techniques (infrared, ultraviolet,
Photography Unit
and X-ray photography) making INVISIBLE INFORMATION
VISIBLE TO THE NAKED EYE.
OPTIONAL SERVICES
Toxicology Unit
Body fluids and tissues are examined for DRUG and ALCOHOL
content
Latent Fingerprint Unit
Examines evidence for latent fingerprints
Polygraph Unit
Administers LIE DETECTOR tests and analyzes the results
Voiceprint Analysis Unit
Analysis of RECORDED THREATS, tape-recorded message.
Crime-Scene Investigation
Collection and preservation of physical evidence done by
Unit
specialists
EXERCISE YOUR BRAIN
In groups, read the following series of situations or examples of evidence. Determine the
appropriate unit that would handle the evidence.
A man arrested for burglary claims he was no where near the scene of the crime.
However, soil found on the bottom of his shoes resembled soil found outside the
window determined to be the point of entry to the house that was robbed.
Which unit in a crime lab tests the soil on his
shoes?
Which unit collects the soil as evidence from
his shoes?
Which unit gives the lie detector test to see if
he is telling the truth?
An envelope containing white powder and a letter was sent to a Senator. The Senator
was in fine health until he received this handwritten, threatening letter.
Name four pieces of evidence you might find in this case, then list the crime units you would
have process the evidence and explain why.
Evidence
Crime Unit
Why
A woman was found dead in an alleyway beside a club. When questioned, the bartender
remembered the woman. According to him, the woman was at the club for a while the
night before with a large group of people, but kept checking her telephone all evening.
Name three crime units you have process the evidence and why
Police investigating an apparent suicide collect the following items at the scene: a note
purportedly written by the victim, a revolver bearing very faint fingerprints, and traces
of skin and blood under the victim’s fingernails.
List the pieces of evidence, unit that would process the evidence, and why
EVIDENCE
UNIT
WHY?
Police arrive at the scene of a robbery and find a broken window in the living room and
smashed photographs. A muddy shoe print was found on the persian carpet.
List the pieces of evidence, unit that would process the evidence, and why
EVIDENCE
UNIT
WHY?
Police arrive at the scene of a motorcycle-SUV collision. They find the body of a John
Doe 15 feet away from the motorcycle. The driver of the SUV reported the motor cyclist
strayed to her side of the road from the other side.
Which crime units would you collect evidence for in this case? Why?
UNIT
WHY?
Come up with your own scenario
.