Forensic Science Unit 1 Test Study Guide

Forensic Science / Criminalistics

Study and application of science to matters of law.

Evidence

Anything that establishes or disproves a fact.

Forensic Specialists

Experts in unique forensic divisions who provide expert witness and impartial opinions.

Odontology

Forensic study of bite marks and dental identification.

Pathology

Forensic study of sudden, unexplained, or violent deaths.

Entomology

Forensic study of insects.

Palynology

Forensic study of pollen and spores.

Polygraphy

Lie detection.

Expert Witness

Testimony provider who must establish credibility through experience, credentials, or background.

Frye Standard

Test determining if evidence is scientific based on general acceptance in the scientific community.

Daubert Ruling

Rule determining if evidence is relevant and reliable by following the scientific method.

Locard Exchange Principle

When two objects contact, material is transferred, directly connecting a criminal to trace evidence.

Statutory Law

Law coming from legislation that declares, commands, or prohibits something.

Common/Case Law

Law coming from judicial precedents and opinions.

Civil Law

Legal disputes involving private parties and relationships regarding property or contracts.

Criminal Law

Regulation and enforcement of rights deemed offensive to society.

Violation

Anytime a law is broken.

Infraction

A minor offense such as jaywalking, littering, or traffic violations.

Misdemeanor

Crime punishable by a fine or up to one year in jail.

Felony

Serious crime punishable by five years to life in prison or the death penalty.

Probable Cause

Reasonable conclusion that a crime was committed by a suspect, preventing arrest without it.

FBI

Federal Bureau of Investigation; owns the largest crime lab in the world.

DEA

Drug Enforcement Administration; operates a crime lab focused on drug-related crimes.

ATF

Bureau of Alcohol, Tobacco, Firearms, and Explosives; runs a lab focused on related crimes and organized crime.

Initial Justice Step

A crime is committed and probable cause is present for an arrest warrant.

Booking Process

Suspect is booked, fingerprinted, photographed, and informed of Miranda Rights.

Arraignment

Court hearing where defendant is formally informed of charges, enters a plea, and learns of bail.

Preliminary Hearing

Court hearing where a judge determines if there is enough evidence and probable cause to continue.

Grand Jury

Panel that decides if a defendant is formally indicted.

Plea Bargaining

Agreement where defendant pleads guilty for a reduced charge or sentence to avoid a full trial.

Testimonial Evidence

Statements made under oath; not always the most reliable form of evidence.

Physical Evidence

Tangible objects or material; generally more reliable than testimonial evidence.

Circumstantial Evidence

Evidence that implies but does not prove a fact, such as fingerprints at a crime scene.

Direct Evidence

Evidence that provides clear proof, such as a BAC over 0.08 or drug possession.

Individual Evidence

Material that can be related to a single source, like fingerprints, DNA, or gun markings.

Class Evidence

Material that can be narrowed down to a group of shared characteristics, like blood type or fibers.

Questioned Sample

Material collected from a known location but of unknown origin.

Known/Control Sample

Material collected of known origin for comparison.

Probative Value

Ability of evidence to prove something that is material to a crime.

Enhancing Class Evidence

Probative value of class evidence is increased when as many different objects are collected.

Crime Scene

The beginning of forensic science that provides useful investigative information.

Modus Operandi (M.O.)

A criminal's method and behavior used to commit a crime.

Police Officer Role

Usually first on scene; prioritizes saving lives and secures the area to prevent evidence loss.

Crime Scene Investigator (CSI)

Documents scene and searches for, photographs, collects, and packages evidence.

Medical Examiner (ME)

Identifies the victim, notifies next of kin, and collects the body for an autopsy.

Detective Role

Interviews witnesses and investigates evidence and leads to identify a suspect.

Securing the Scene

Prioritizing saving lives while protecting the scene from unauthorized access and contamination.

Common Approach Path

Designated path for personnel to enter and exit a crime scene to prevent contamination.

Spiral Search Method

Used for large areas where one person spirals inward and another spirals outward.

Strip/Parallel Search Method

Used for smaller areas where people start on opposite ends and walk in parallel lines.

Grid Search Method

Used for areas with heavy debris where searchers cross paths at right angles.

Quadrant/Zone Search Method

Used for smaller areas broken down into specific zones.

Documenting the Evidence

Recording via notes, photography, sketching, and videos before touching anything.

Crime Scene Sketching

Measuring evidence from its center to two nearest walls at right angles to record spatial relations.

Chain of Custody

Written record tracking who has possession of evidence at all times from collection to court.