Download Unit 1 - Introduction to Forensics

How observant are you?
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The application of the scientific method and techniques to law and
criminal justice
Encompasses many fields: chemistry, physics, biology, earth science,
math, psychology
Understanding the science behind crime scene detection
Use evidence to establish or disprove facts to influence the beliefs of
an observer (judge or jury) to determine guilt or innocence
Forensic evidence is aimed at informing the court where it lacks
expertise
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Mathieu Orfila :the father of
forensic toxicology.
Alphonse Bertillion :devised
the first scientific system of
personal identification in 1879
Edmond Locard :incorporared
Gross’ principles within a
workable crime laboratory.
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Locard’s Exchange Principle
states that when a criminal
comes in contact with an
object or person, a crosstransfer of evidence occurs
1. Physical Science Unit
Chemistry (drugs,
explosives)
 Physics (glass, scratches)
 Geology (soil, rocks)
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2. Biology Unit
Bloodstains
 Body fluids
 Hair and fiber
 Botanical materials
(wood/plants)
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3. Firearms Unit
Firearms
 Bullets
 Cartridge & shells
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4. Photography/Document Unit
Handwriting
 Computer applications
 Pictures/ink
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Examine the evidence
Perform the appropriate
analysis or measurement
Render a conclusion based
on evidence
Testify in court
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Found at the local, state, and federal levels…approximately 320 crime
labs operate at various levels of government
FBI: Federal bureau of Investigation
DEA: Drug enforcement agency
AFT: Alcohol, tobacco, firearms
Statutory Law
 A law or group of laws passed by a legislature or other official governing
bodies…abolishing or creating government programs
Common law
 Laws developed by judges through decisions of courts not imposed by
government officials
Civil law
 Laws dealing with disputes between individuals and/or organization, in
which compensation may be awarded to the victim
Criminal law
 The body of rules that defines conduct that is prohibited by the state
because it is held to threaten, or harm the safety of the public
Administrative law
 Laws that governs the activities of administrative agencies of
government…IRS
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Scientific evidence is aimed at
informing the court where it
lacks expertise
Assist in determining fact
Under due process the
government cannot take away
your life, liberty, or property
without probable cause (the
standard by which an officer
or agent has the grounds to
make an arrest, to conduct a
personal or property search,
or to obtain a warrant for
arrest)
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Crime is committed
Suspect is arrested and booked: A procedure that requires
information about the suspect..photographed, fingerprinted, and
a line up
Suspect given Miranda rights
Suspect is brought before a judge for arraignment…charges and
enters a plea (guilty or not guilty)
A guilty suspect us then brought to a preliminary hearing to
determine if the suspect should be charged with the crime and
should be held for trial, and if bail should be set
If the suspect is indicted (accused of crime) a trial is set
A plea bargain can occur in which the suspect and prosecution
work out a deal without going to trial
1. Infractions
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A minor offense or petty crime
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The penalty is usually a fine
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Traffic violations
Littering
2. Misdemeanor
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A minor crime punishable by no more than a year in jail
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DWI
Shoplifting
Vandalism
3. Felony
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Serious crimes that are punishable by no more than 1 year in prison up to death by
execution
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Murder
Robbery
Arson