Download Class #3

CSI: Gervais
Starring . . .
Alejandro Cruz
Esmeralda Gomez
Ivan Gonzalez
Elesei Kalugin
Olivia Marshall
Mayra Niniz
Amber Pate
Chris Ramsey
Zach Sandvig
“Brian” Siriwannahong
Teresa Tello
John Wagner
Forensic Techniques
DNA Evidence
• Body fluids, such as
blood, and saliva, are
commonly used in
forensic investigations
as a source of cells
for DNA extraction
and analysis.
•
http://www.courttv.com/forensics/lab/
A distinctive DNA print from a crime
scene when matched to suspect's
DNA print can place a suspect at
the crime scene.
Bite Marks
A dental expert, or forensic
odontologist, has numerous
roles, one of which is to
match the bite-mark
impressions on a victim to
the tooth structure of
suspects. Teeth are tools
and a tooth mark is like a
tool mark. Generally the
teeth that leave the
strongest impressions are
in the front, both top and
bottom.
http://www.courttv.com/forensics/lab/
Fingerprinting
Fingerprints are the unique patterns created by
skin ridges found on the palm sides of fingers and
thumbs. It is one of the most useful evidence
pieces in forensic science.
http://www.courttv.com/forensics/lab/
Firearm Comparison
Sometimes incorrectly referred to as
ballistics, firearms identification can be
defined as, ”The identification of fired
bullets, cartridge cases or other
ammunition components as having been
fired from a specific firearm.”
http://www.courttv.com/forensics/lab/
Time of Death (TOD)
Medical
investigators look for
various signs to help
them estimate a time
frame -- usually a 2
to 4-hour window of
time -- in which the
victim probably died.
http://www.pathguy.com/TimeDead.htm
http://www.courttv.com/forensics/lab/
Fiber Comparison
Placing a suspect at the scene
of a crime is an important
element in criminal
investigation. This can be
achieved through the location
of fibers similar to those from
the victim's clothing or the
crime scene on the clothing of
the suspect, or through the
discovery of fibers like those in
the suspect's clothing at the
crime scene. This can also be
done with hair.
http://www.courttv.com/forensics/lab/
Carpet fiber
Two matching hairs
identified with the
comparison microscope
Ritualistic Behavior
Investigators look to see whether a
crime's method of operation, or MO,
was the same or different, and
whether either or both crimes
involved any ritualistic behaviors
that could be used to characterize
the suspect.
http://www.courttv.com/forensics/lab/
Shoeprints and Casting
Characteristics that result
when something is randomly
added to or taken away from
a shoe outsole that either
causes or contributes to
making that show outsole
unique
Casting can retrieve a threedimensional footwear
impression.
http://www.courttv.com/forensics/lab/
Sneaker print with 10 distinctive
characteristics creates a
fingerprint of the shoe.
Blood Spatter
The impact of spilled
blood on surfaces. The
patter of the impact can
provide vital information
about the source of the
blood. Blood spatter can
help determine the size
and type of wounds, the
direction and speed with
which the perpetrator or
victim was moving, and
the type of weapons
used to create the blood
spill. http://www.courttv.com/forensics/lab/
http://www.bloodspatter.com/BPATutorial.htm
Accelerants
Investigators can prove
that a fire was set
intentionally by finding an
accelerant at the scene of
a fire. An accelerant is a
chemical fuel that causes
a fire to burn hotter,
spread more quickly than
usual, or be unusually
difficult to extinguish. The
presence of an accelerant
in fire debris can be used
as evidence of arson.
http://www.courttv.com/forensics/lab/
There are many,
many, many more
topics of forensics!
CheCk out a Book, take CCC’S
forensics class, look on the
internet, and pass your
science classes!