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WHAT IS FORENSIC SCIENCE?
WHAT IS FORENSIC SCIENCE?
Forensic Science is the application of science to
those criminal and civil laws that are enforced by
police agencies in a criminal justice system.

Forensic
Science
Law
Science
LAW ASPECTS OF FORENSIC SCIENCE
Lawyers
Police Officers
Detectives
FBI Agents
ATF
DEA
SBI
CCBI
SCIENCE ASPECTS OF FORENSIC SCIENCE
Chemist
 Toxicology
Biology
Serololgy
DNA
Body Prints
Time of Death
Physics
Ballistics
Tool Marks
Medical
Medical Examiner
Pathologist
Geology
Soil
Water Diodes
Soil Layers
HISTORY AND DEVELOPMENT OF
FORENSIC SCIENCE
MATHIEU ORFILA (1787- 1853)
Considered to be the father of forensic
toxicology
Toxicology deals with the study of the
adverse effects of chemicals on living
things.
ALPHONSE BERTILLON (1853-1914)
Developed anthropometry.
Anthropometry is a systematic procedure
for taking body measurements for the
purposes of personal identification.
Known as the Father of Criminal
Identification.
FRANCIS GALTON (1822-1914)
First to determine that fingerprints could
be used for identification.
LEONE LATTES (1887 – 1954)
Developed a technique to determine
blood type(A, B, AB or O) from a dried
blood stain.
CALVIN GODDARD (1891-1955)
Developed the comparison microscope.
A comparison microscope is used to
examine side by side samples.
The comparison microscope is mainly
used to analyze bullets, bullet casings
and bullet shells.
ALBERT S. OSBORN (1858 – 1946)
Developed the fundamental principles
of document examination.
His work included the identification of
handwriting, typewriting, paper, and ink.
WALTER C MCCRONE (1916 – 2002)
A prominent microscopist
Determined Turin Shroud was a
medieval painting.
HANS GROSS (1847 – 1915)
Father of Criminalistics
First Institute of Criminology
EDMOND LOCARD (1877- 1966)
Referred to as the “Sherlock Holmes of
France”
Studied alongside Bertillon.
Developed the science of poroscopy, the
study of fingerprint pores and the
impressions left by these pores.
J. EDGAR HOOVER (1895-1972)
First director of the FBI
AUGUST VOLLMER
Father of Law Enforcement
Developed Crime Lab Model
PAUL KIRK (1902- 1970)
Scientific Process of crime scence
investigation
Known for his work with blood splatter
patterns
The Fugitive – Sam Sheppard case
EVIDENCE AND COLLECTION OF EVIDENCE
ORDER OF PROCESSING A CRIME SCENE
1. Secure the scene
Ropes, Barricades, Tape and Guards
2. Lead Investigator evaluates the scene.
 Overview the scene
Develop strategy to document and collect evidence
Determine search method to be used.
3. Record the scene
Photographs
Sketches – to scale, labels…..
Notes – descriptions of evidence and locations
EVIDENCE AND COLLECTION OF EVIDENCE
4. Search for evidence
Spiral, Grid, Line or Quadrant
Vehicle – outside, under, inside
5. Collect and package evidence.
Prevents any changes between scene and lab
Separate containers for different items or items collected from different locations
Caution with airtight containers – samples grow mold
Maintain chain of custody
THE PURPOSE OF FORENSIC SCIENCE
The purpose of forensic science is to uncover evidence that stands
as fact.
Uses science to help in legal matters, such as crimes.
The job of the forensic scientist is to….
1. Collect and examine physical evidence
2. Report this to investigators and possibly later in court
THE JOB/ROLE OF A FORENSIC SCIENTIST
The job of the forensic scientist is to….
1. Collect and examine physical evidence
2. Report this to investigators and possibly later in court
WHERE DOES THE SCIENTIFIC METHOD FIT?
Deductive reasoning
CRIME LABS
August Vollmer established the first crime lab in 1924 in Los Angeles.
The FBI did not set up their own crime lab until 1932.
MAJOR COMPONENTS OF A CRIME LAB
Physical Science Unit
Applies principles and techniques of chemistry, physics and geology
to the identifications and comparison of crime-scene evidence.
Staffed by scientists that have an expertise in the use of chemical tests
and modern analytical instrumentation for the examination of items
such as drugs, glass, paint, explosives and soil.
This unit could be further subdivided into drug identification, soil and
mineral analyses and examination of a variety of trace physical
evidence.
Biology Unit
Staffed by biologists and biochemists who work with:
1.
identification and DNA profiling of dried blood stains and other body
fluids,
2. Comparison of hairs and fibers
3. Identification of botanical materials such as wood and plants
Firearms Unit
Examine firearms, discharged bullets, cartridge cases, shotgun shells and
ammunition of all types.
Examine garments and other objects in order to detect discharge residues
Approximate the distance from a target at which a weapon is fired
Comparisons are also made to tool marks.
Document Examination Unit
Study the handwriting and typewriting on questioned documents to
determine authenticity and/or source.
Analysis of paper and ink, indented writings, obliterations, erasures and
burned or charred documents.
Photography Unit
Examine and record physical evidence
Digital imaging, infrared, ultraviolet and X-ray photography may be used to
make invisible information visible to the naked eye.
Aids in the preparation of photographic exhibits for courtroom presentation.
OPTIONAL SERVICES PROVIDED BY CRIME LABS
TOXICOLOGY UNIT
Body fluids and organs are
examined to determine presence or
absence of drugs and poisons.
Field units such as a Intoxilyzer are
used to determine the alcoholic
consumption of individuals. This
section is often responsible for
training operators as well as
maintaining and servicing these
instruments
LATENT PRINT UNIT
Responds to the scene of the
crime and collects, preserves,
processes and examines
physical evidence for the
presence of footwear and tire
impressions, fingerprints, palm
prints, foot prints and physically
match them.
POLYGRAPH UNIT
Polygraph = Lie
detector
Seen more as a tool
for a criminal
investigator. A few
remain in the crime lab.
VOICEPRINT ANALYSIS UNIT
These individuals tie the
voice of a particular suspect
to telephoned threats or
tape-recorded messages.
Sound spectrograph is
used. This transforms
speech into a visual graphic
display called a voiceprint.
THE FUNCTIONS OF A FORENSIC
SCIENTIST
ANALYSIS OF PHYSICAL EVIDENCE
Must be a skilled scientist
Procedures and techniques must rest on a firm scientific
foundation while satisfying the criteria of admissibility that
have been established by the courts.
PROVISION OF EXPERT TESTIMONY
May be asked to serve as an expert witness.
Courts rely on training and years of experience as a
measurement of the knowledge and ability of the expert.
Opposing attorney must be given the opportunity to
cross-examine the expert witness and point out weakness
in background and knowledge prior to the judge rules on
a witness’s qualifications.
Must remain impartial and an advocate of the truth.
PROPER TRAINING
Every individual involved in field collection must be
trained in the area of proper-evidence collection.
Proper tools and supplies must be made available
for the proper collection and packaging of evidence
for future scientific examination.
OTHER FORENSIC SCIENCE SERVICES
FORENSIC PATHOLOGY
Involves investigation of
sudden, unnatural,
unexplained, or violent
deaths
Take on the role as a
medical examiner or
coroner
PRIMARY ROLE OF A MEDICAL EXAMINER
Answer the following
questions?
Who is the victim?
What injuries are present?
When did the injuries occur?
Why and how were the
injuries produced?
So that the cause of death
can be determined.
If the cause of death can
not be determined, an
autopsy is performed.
CLASSIFICATION OF MANNER OF DEATH
Natural
Homicide
Suicide
Accident
Undetermined
TIME OF DEATH DETERMINATION
The following are used to determine the time of
death:
Rigor mortis
Livor mortis
Body Temperature
Eye Appearance
Stomach Contents
RIGOR MORTIS
Immediately following death, the muscles relax and then
become rigid without shortening the muscle.
Appears within the first 24 hours and disappears within
36 hours
LIVOR MORTIS
Blood settles in the parts of the body closest to the
ground.
Due to the heart no longer pumping
Skin will appear dark blue or purple in color
This condition begins immediately and continues for up to
12 hours after death.
BODY TEMPERATURE
Algor mortis – process in which the body
temperature continually cools after death until it
reaches the ambient or room temperature.
Rate of heat loss is influenced by location and size
of the body, victim’s clothing and weather conditions.
General rule = body begins losing heat at a rate
of 1 to 1 ½ degrees Fareinheit per hour until it
reaches the temp of the environment.
EYE APPEARANCE
Determining potassium levels in the ocular fluid (vitreous
humor)
After death, cells within the inner surface of the eye
release potassium into the ocular fluid.
Analysis of the amount of potassium at various intervals
after death allows a rate of potassium release to be
established. This rate allows the approximate time of
death to be determined.
EYE STRUCTURE
STOMACH CONTENTS
Amount of food in the
stomach can help to
estimate when a person’s
last meal was eaten.
FORENSIC ANTHROPOLOGY
Deals primarily with the
identification and
examination of human
skeletal remains.
Skeletal remains can last
decades and even
sometimes centuries.
FORENSIC ANTHROPOLOGY
Examination of bones can reveal:
Origin
Sex
Approximate age
Race
Skeletal injury
FORENSIC ANTHROPOLOGY
May also be useful in
creating facial
reconstructions.
FORENSIC ENTOMOLOGY
Deals with the study of insects and their relation to
criminal investigation.
Used to estimate the time of death when the
circumstances surrounding the crime are unknown.
After decomposition begins, blow flies are the first insect
to infest the body.
FORENSIC ENTOMOLOGY
Life cycles are influenced
by environmental factors
such as geographical
location, climate and
weather conditions.
FORENSIC PSYCHIATRY
Criminal Cases
Civil Cases
Evaluate behavioral
disorders and determine
whether people are
competent to stand trial.
Determine whether people
are competent to make
decisions about preparing
wills, settling property or
refusing medical treatment.
FORENSIC ODONTOLOGY
Provide information about the identification of victims
when the body is left in an unrecognizable state.
Use teeth structure to compare to dental records to
identify a person.
May also analyze bite marks.
Many assault cases involve bite marks left on the victim.
FORENSIC ENGINEERING
Concerned with the failure analysis, accident
reconstruction and causes and origins of fires or explosions.
Questions they answer:
How did an accident or structural failure occur?
Were the parties involved responsible? If so, how were they
responsible?