Download An Introduction to Forensic Science

An Introduction to Forensic
Science
What is Forensics?
• Forensic science is the application of
science to those criminal and civil laws
that are enforced by police agencies in
a criminal justice system.
Brief History of Forensic Science
• 1800’s Sir Arthur Conan Doyle’s Sherlock Holmes
adventure stories.
• 1903 New York State prison initiates the use of
fingerprints to identify criminals
• 1923 Los Angeles Police Department (LAPD)
formed the first crime laboratory
• 1932 Federal Bureau of Investigation (FBI)
crime laboratory was created
• 1948 University of California at Berkeley opens
the school of criminology
• 1960’s Drug use is on the rise – more drug
testing
Increase in Crime Rate
• Science is involved in monitoring water
quality, nature and potency of drugs, etc…
• With the increase in population and crime
rate, more science is applied – example:
drug testing and detection, DNA, etc…
• More and more laws regulate and restrict
us and science is involved in this
regulation and restriction.
What is a Crime?
• CRIME: An offense against the public at
large, proclaimed in a law and punishable
by a governing body
• CRIMINAL LAW: The body of law
that, for the purpose of preventing
harm to society, defines what behavior
is criminal and prescribes the
punishment to be imposed for such
behavior
A death that is unexpected or is
thought to have been caused by injury
or poison, is always investigated for
the purpose of determining whether it
was a homicide.
A homicide is a death caused by
an act of another , which was
done with intent to produce
bodily injury, or death or done
with disregard for the possibility
that it could produce injury or
death
Suicide is the act of taking one's own
life on purpose.
Classification of Crimes?
• FELONY: A relatively serious criminal
offense punishable by death or
imprisonment for more than a year in a
state or federal prison
• MISDEMEANOR: A less serious crime
that is generally punishable by a prison
sentence of not more than one year in a
county or city jail
The Law, Evidence & the
Analyst
• The forensic scientist or criminalist has
no function without the judicial system
• The criminalist’s job is to:
– provide scientific info to the legal
community (expert witness testimony)
– translate the story the evidence has to tell
• Analysis is done only at the behest of
someone seeking to introduce the
evidence into a court of law
(prosecution or defense)
The Role of a Criminalist
• A criminalist obtains data or evidence
by two methods
– qualitative data by observation
– quantitative data by measurement
• From this evidence
– The criminalist uses logic and/or reasoning
when evaluating the evidence and attempts
to understand and reconstruct the crime
Questions:
 What does a forensic scientist do?
Some Jobs in Forensic Science
 Investigation
 Laboratory Work
 Crime Scene Work
 Performing Autopsies
Investigation of Crime
The police investigate crimes.
Forensic scientists do not investigate.
Laboratory Work
Scientists conduct laboratory analysis.
Police investigators do not work in the lab.
Forensic Scientists in the Lab
 Fingerprinting
 Firearms/ Ballistics
 Documents
 Trace Evidence (i.e.
Hair, Fiber)
 Blood Splatter/
DNA
 Drugs/ Toxicology
 Bones/Teeth/Bugs
Crime Scene Work
Who performs work at the crime scene?
What do they do at the crime scene?
Crime Scene Work
Police or Crime Scene Technician may
collect evidence
Crime Scene Work
Crime Scene Tech only processes evidence.
Does not investigate or conduct lab work.
Crime Scene Work
Crime Scene Tech only processes evidence.
Does not investigate or conduct lab work.
Fact:
CSI: Fact or Fiction?
Crime scene investigators do exist.
 Investigation system varies from region to
region

The Fiction:
They do too much!
 Not very likely that they dramatically
communicate with the victims or suspects

Note about Crime Scene Work:
Some, but not all, forensic scientists
work crime scenes
 System varies from region to region
 Crime or death scene investigator is a
real job

Landing your ideal job requires patience
and the ability to relocate.
Many fields of study have forensic
applications:





Forensic
Forensic
Forensic
Forensic
Forensic
Entomology
Anthropology
Odontology
Pathology
Psychology
Forensic scientists in these fields are
educated in the general field, then
specialize in the forensic application of the
science.
Questions:

Where would I work?

What education do I need?

How easy is it to get a job and how
much money can I make?
Where would I work?
1. State Agency
 State Police
 State Bureau of Investigation
 County or City Crime Labs
2. Federal Agencies
 FBI
 ATF
 Secret Service
(Dept of Alcohol, Tobacco &
Firearms)
 DEA
(Drug Enforcement
Agency)
 Armed Forces  U.S. Postal Service
Where would I work?
3. Private Labs
 Private DNA Labs
 Paternity Labs
 Drug Analysis
4. Non Forensic Laboratories
 Analytical
Chemistry
 Research Labs
 Pursue an advanced
degree
Undergraduate Education:
What’s my major?
Myth: Forensic Science is half science
and half criminal justice
Fact: Forensic Science is mostly
science
Undergraduate Education
Chemistry or Biology (B.S.)
Forensic Science (B.S.)
(also Forensic Chemistry or Forensic Biology)
B.S. in Forensic Science may help, but does
not guarantee a job after undergrad.
http://www.youtube.com/watch?v=DNVa5e51
FE8 (30 sec ad)
FORENSIC SCIENTIST I, II, or III
(Posted 8/11/06)
The Texas Department of Public Safety is seeking applicants for the position of
Forensic Scientist I, II, or III. Qualifications include graduation from an accredited
four-year college or university with a major in biology, chemistry, or forensic science,
including the successful completion of 16 semester hours of chemistry and a minimum
of one 3-semester-hour course each in genetics, upper division molecular biology
(molecular genetics), and biochemistry (transcripts required). Applicants must be
skilled in the use of laboratory equipment/materials. Responsibilities include conducting
analyses/examinations of tissue/body fluids of human/animal origin to detect the
presence of blood stains/semen/other stains; examining/comparing hairs to establish
origin/descriptive characteristics; conducting DNA typing tests on human tissues to
compare criminal evidence with samples of known origin;
evaluating/interpreting/documenting the DNA test conducted and testifying in court as
to the findings; appearing at crime scenes to collect evidence and assist law
enforcement officers; preparing reagents; reviewing work of other forensic scientists;
maintaining records of evidence and its disposal; performing proficiency tests and
other quality assurance duties; participating in continuing education; and performing
other duties as assigned. On the job training will be provided for a period of about six
months. All applicants must be U.S. citizens. Annual Salary: $39,312. Applicants may be
compensated at a higher level when hired depending on previously qualifying Crime
Laboratory work experience. Application deadline: August 23, 2006.
http://www.txdps.state.tx.us
Interview Process:
Extensive Background Check
Past Landlords
 Past Employers

Polygraph
Relatively Strict on Past Drug Use
Job Availability:
10,000 positions to fill,
but no money to pay employees.
Flexibility in relocation greatly enhances
your chances of getting a job.
Basic Areas of a Criminology Lab
•
•
•
•
•
•
•
•
•
•
Physical Science Unit
Biological Unit
Firearms Unit
Photography Unit
Toxicology Unit
Document Examination Unit
Fingerprint Unit
Polygraph Unit
Voiceprint Analysis Unit
Evidence Collection Unit
Types of Evidence
1. Testimonial evidence would be any
witnessed accounts of an incident or crime.
2. Physical evidence refers to any material
items that would be present on the crime
scene or the victims. These items would be
presented in a crime investigation to prove
or disprove the facts of the issue.
• Trace evidence refers physical evidence that
is found at a crime scene in small but
measurable amounts (can be anything from
strands of hair or skin cells to tool marks).
Trace evidence can be used to identify a
victim or suspect or determine how a crime
was committed.
Evaluating the Evidence
All physical evidence and trace evidence is
circumstantial
• Circumstantial evidence can be used to infer
someone’s guilt
• The more physical evidence present in a case
the more likely the offender accused will be
found guilty
• Eyewitness evidence tends to be considered
conclusive unless the witness is not credible
Videos
10 Crimes Caught on Google Earth (4 min)
https://www.youtube.com/watch?v=5EaZIpqIjK8
10 Crimes Caught on Google Street View (7 min) begin at :45
https://www.youtube.com/watch?v=LSSfOwBTDhw
Digital evidence forensics (3.5 min)
https://www.youtube.com/watch?v=vfxEAp93zWg
WORKING IT: Digital Forensics Detective (3 min)
https://www.youtube.com/watch?v=Kvvfj-Fn2go
A Look At Digital Forensics Bloomsburg University (3 min)
https://www.youtube.com/watch?v=ZpSfcVE-_To