Download Photography Unit

Crime Scene
Specialties
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Crime Lab — Basic Services
 Physical Science Unit
 Chemistry
 Physics
 Geology
 Biology Unit
 Firearms Unit
 Document Examination
Unit
 Photography Unit
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Most crime labs are
backlogged and there has
been a “triage” system
developed to help analyze
the sample from the most
“serious” cases, murder &
sexual assault
Physical Science Unit
Crime Lab —Basic Services
Applies principles of chemistry, physics and
geology to identify and compare physical
evidence such as:
• Drugs
• Glass
• Paint
• Explosives
• Soil
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Biology Unit
Crime Lab—Basic Services
Applies knowledge of biological sciences to
investigate samples such as:
• Blood
• Body fluids (DNA)
• Hair
• Fibers
• Botanical samples
(ex. wood, plants)
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Firearms Unit
Crime Lab—Basic Services
Examines:
• Firearms
• Discharged bullets
• Cartridge cases
• Shotgun shells
• Ammunition of all types
• Garments and other objects for
firearms discharge residues
• Approximate distance from target
to weapon
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Document Examination Unit
Crime Lab—Basic Services
• Studies handwriting and typewriting on questioned
documents to determine authenticity and/or source
• Analyze paper and ink
• Examine indented writings, obliterations, erasures and
burned or charred documents
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Photography Unit
Crime Lab—Basic Services
Use of highly specialized photographic
techniques to make invisible information visible
to the naked eye, such as:
• Infrared
• Ultraviolet
• X-ray photography
Photographs crime scenes and physical evidence
Prepares photographic exhibits for court
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Photography Unit
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Optional Services Provided by FullService Crime Lab
• Fingerprint Unit & Latent Fingerprint processes and
examines evidence for latent fingerprints.
• Polygraph Unit conducts polygraph or lie detector
tests.
• Voiceprint Analysis Unit attempts to tie a recorded
voice to a particular suspect.
• Evidence-Collection Unit dispatches specially trained
personnel to the crime scene to collect
and preserve physical evidence.
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Several Units coming together on 1 piece of evidence
An envelope containing anthrax spores along with an anonymous letter was sent to the office of Senator
Tom Daschle shortly after the terrorist attacks of September 11, 2001. A variety of forensic skills were used
to examine the envelope and letter. Also, bar codes placed on the front and back of the envelope by mailsorting machines contain address information and information about where the envelope was first
processed. Courtesy Getty Images, Inc.—Liaison
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Special Forensic Science Services
 Forensic Pathology
 Forensic Entomology
 Forensic Odontology
 Forensic Anthropology
 Forensic Toxicology
 Forensic Psychiatry
 Forensic Engineering
 Forensic Computer and Digital
Analysis
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Forensic Pathology
Concerned with
determining the
cause of death
A forensic
pathologist
examines a
kidney during
an autopsy.
Examines
wounds and
injuries
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“This is the place where the dead
shall teach the living.”
Forensic Entomology
• Uses insects to help law enforcement determine the cause,
location and time of death (TOD) of a human being
• Insect life cycles act as precise clocks which begin within
minutes of death
• Used to determine the TOD when other methods are useless
• Insects can also show if a body has been moved after death
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Forensic Odontology
• Helps identifies victims based on dental evidence
• Bite mark analysis - compare marks left of a victim and the
tooth structure of a suspect
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Bite Marks
Pattern injury displaying ovoid
pattern and central bruising
Pattern injury displaying linear
interrupted abrasions
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Forensic Anthropology
• Assist in identification of deceased individuals whose
remains are decomposed, burned, mutilated or otherwise
unrecognizable
An anthropologist exhumes an unidentified
set of remains from a Sarajevo cemetery.
Forensic anthropology teams match these
and thousands of other remains from
conflicts around the world with DNA
samples from family members of missing
relatives. Photo by T.J. Grubisha 2002,
U.S. State Department.
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Forensic Toxicology
• The effects of poisons, toxins and drugs in the body.
• Blood & breath alcohol determination
• Urine & hair testing for a “drug-free workplace”
• “Date rape” drugs in a sexual assualt victim
• Not to be confused with “drug” analysis in the
physical crime unit. Drug analysis is simply
identifying the substance
• For example: is this white powder in fact cocaine
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Forensic Psychiatry
• Examines relationship between human behavior and legal
proceedings is examined
• Determine if person is competent to stand trial
• Examines behavior patterns of criminals as an aid to
developing a suspect’s behavioral profile
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Forensic Engineering
Concerned with
•
failure analysis
• accident reconstruction
• causes and origins of fires or explosion
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Forensic Computer Science + Digital Analysis
• Identifying, collecting, preserving, and examining
information derived from computers and other digital
devices, such as cell phones
• Recovering deleted or overwritten data from a computer’s
hard drive
• Tracking hacking activities within a compromised system
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Expert Witness
Everyone of these specialists could be an expert witness
called to testify in court about the work they or someone
else conducted in the lab.
They are individuals who by knowledge, training or
experience are qualified to discuss their experiences in
court
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Dr. Henry Lee
Dr. Lee was an expert witness for several high profile cases, he is
also one of the authors of your textbook
http://www.youtube.com/watch?v=u26d8W5i2JU
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Dr. Jan Garavaglia (Dr. G)
Dr. G’s (expert medical examiner) testimony during the
Casey Anthony Trial in the death of Caylee Anthony her
two-year old daugher who was missing for 31 days prior
to contacting the police.
http://www.youtube.com/watch?v=ybNUo2EM7b8
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