Forensic Science Vocab

Autopsy

The internal and external examination of a body after death. An autopsy is performed to confirm or determine the cause of death and establish other pre-death conditions, such as the type of food last consumed and the time it was consumed.

Ballistics

The study of the motion of bullets and their examination for distinctive characteristics after being fired. Examiners can use this evidence to match bullets or bullet fragments to specific weapons.

Blood Splatter

The pattern of blood that has struck a surface. This pattern can provide vital information about the source of the blood. Can help determine the size and type of wound, the direction and the speed with which the perpetrator or victim was moving, and the t

Caliber

The diameter of the bore of a rifled firearm, usually expressed in hundredths of an inch or in millimeters.

Composite Drawing

A sketch of a suspect produced from eyewitness descriptions of one or more persons.

Criminology

The study of criminal activity and how it is dealt with by the law.

DNA

Deoxyribonucleic acid. Double helix strand. Genetic code (fingerprint). 50% from mom and 50% from dad. ACGT.

DNA Electrophoresis

The technique by which DNA fragments are placed in a gel and charged with electricity. An applied electric field then separates the fragments by size, as part of the process of creating a genetic profile.

DNA Profiling

The process of testing to identify DNA patterns or types. In forensic science this testing is used to indicate parentage or to exclude or include individuals as possible sources of bodily fluid stains (blood, saliva, semen) and other biological evidence (

Evidence

Anything that has been used, left, removed, altered, or contaminated during the commission of a crime or other event under investigation

Fingerprint

The unique patterns created by skin ridges found on the palm sides of fingers and thumbs.

Forensic Science

The application of science to law. The application of science to those criminal and civil laws that are enforced by police agencies in a criminal justice system. The focus of forensics is the crime lab. The crime lab uses the principles and technique of b

Gas Chromatograph (GC)

A forensic tool used to identify the chemical makeup of substances used in the commission of crimes. The questioned substance is burned at high temperatures. The temperature at which this material becomes gas is then charted to determine its makeup.

Gene

A unit of inheritance consisting of a sequence of DNA that determines a particular characteristic in an organism.

Hemoglobin

A red blood cell protein responsible for transporting oxygen in the bloodstream. Provides the red coloring of blood.

Latent fingerprint

A fingerprint made by deposits of oils and/or perspiration, not usually visible to the human eye.

Lie Detector

A machine that charts how respiration and other bodily functions change as questions are asked of the person being tested. Also known as a polygraph. An attempt to knowingly provide false answers can cause changes in bodily functions.

Luminol

A chemical that is capable of detecting bloodstains diluted up to 10,000 times. Is used to identify blood that has been removed from a given area.

Physical Evidence

Any object that can help explain an event under investigation, Can establish that a crime has been committed, and Sometimes can provide a link between a crime and its victim or between a crime and its perpetrator.

Ridge Characteristics

Ridge endings, bifurcations, enclosures, and other ridge details, which must match in two fingerprints for their common origin to be established.

Serology

A technology dealing with the properties and actions of serums in blood

Super Glue Fuming

Techniques used to develop latent fingerprints on non-porous surfaces. A chemical in the glue reacts with and adheres to the finger oils, and then exposes latent prints.

Toxicology

The study of poisons and drugs and their effect on human and animal populations. It is the study of symptoms, mechanisms, treatments and detection of poisoning, especially the poisoning of people.

Trace Evidence

Material deposited at a crime or accident scene that can only be detected through a deliberate processing procedure. An individual entering any environment will deposit traces of his or her presence, and this material can be used as evidence. Examples- ha

Trajectory

The path of a projectile. A trajectory can be described mathematically either by the geometry of the path, or as the position of the object over time.

Locard's Exchange Principle

Dr Edmund Locard, a French police officer and forensic scientist. Any physical contact between a suspect and victim will result in physical evidence being exchanged between them.

Mass Spectrometry

A technique used by toxicologist to identify chemical compositions. The instrument breaks a chemical down into its ions and accelerates them in a magnetic field that produces a unique spectrum.

Mitochrondrial DNA (mtDNA)

Used to trace ancestry. Type of DNA located in the mitochondrion of most cells. Last longer than nuclear DNA. Only comes from the mother

Nuclear DNA

The unique DNA that is inherited from each parent

Modus Operandi (MO)

The usual method of operation used by a perpetrator. Particular weapon used or taking "trophy" items from victims

Professional Witness

A professional person who testifies at a trial. Police officer or security guard

Reenactment of a crime

The use of ordinary people or actors to recreate a crime.

Reconstruction of a crime

Determining the way a crime happened, pieced together using evidence at the crime scene.

Antemortem

Before death

Perimortem

At or around the time of death

Postmortem

After death

Presumptive test

Cheap, simple test that shows that a sample probably contains the substance the test aims to identify

Suspect

An individual who might possibly have committed the crime under investigation. Guilt is presumed or has been proven

Coroner

Public official who is responsible for investigating any death that may not have had a natural cause

Medical Examiner

Trained medical practitioner who devotes some or all of their time to forensic work

Odontology

Forensic dentistry

Pathology

The study of the causes and consequences of disease and injury in relation to crime and the law

Abrasion

An injury in which the skin has been scraped off.

AFIS

Automated Fingerprint Identification System. Scans fingerprints electronically and plots the positions of their ridge characteristics, comparing them with prints in a database.

Arches

Fingerprint ridges that rise above one another at their center like an arch.

Whorls

Fingerprint patterns that resemble small whirlpools revolving around a point.

Loops

Fingerprint patterns consisting of ridges that double back on themselves.

Cadaveric Spasm

A type of instant rigor mortis in which muscle stiffness occurs just after death because the muscles were being used with great exertion while dying.

CART

Computer Analysis and Response Team; FBI; Examines computers during investigations.

CCTV

Closed-circuit television; Surveillance camera used to record crimes being committed, to find lost persons, or to prevent crime.

Chain of Custody

A list that records every official person who handles a piece of evidence. Those in the chain put their initials and the date on the evidence container.

CODIS

Combined DNA Index System (FBI). Used to share DNA profiles kept in the FBI's National DNA Index System (NDIS) with law enforcement bodies.

Cold Case

An old unsolved criminal case. Many are now being solved with the advent of DNA test.

Comparison Microscope

A microscope that has two compound light microscopes with an optical bridge, so that two samples can be viewed in a single eyepiece. It is used to match trace evidence such as fibers and bullet casings.

Contamination

The act of ruining evidence by accidentally depositing outside trace evidence, including DNA, on items from a crime scene or suspect.

Contusion

A bruise in which the skin is not broken.

CPR

First aid method of cardio-pulmonary resuscitation. Mouth-to-mouth resuscitation is combined with chest compressions.

Expert Witness

A specialist witness, such as a forensic scientist, who testifies at a trial.

FISH

Forensic Information System for Handwriting. A database for handwriting samples

FOA

First officer attending a crime scene

Fracture

A break, crack, or shattering of a bone

Genome

The complete set of DNA within a cell

Henry System

A system used for classifying 10-fingerprint collections. Developed in 1899 by Sir Edward R. Henry with the British police in India

IAFIS

Integrated Automated Fingerprint Identification System (FBI's). Police forces can submit samples to be compared to those on this computerized database

Laceration

A cut that is deep enough to need stitches

ADH

Accumulated degree hours. Time x temp. Amount of energy required for insects to move from one developmental stage to the next.

TOD

Time of death, The time a body died

PMI

Postmortem interval, Time since death

DOA

Dead on arrival

PCR

Polymerase chain reaction. A "molecular photocopying" technique that amplifies specific regions of a DNA strand, used to copy DNA

SOCO

Scene of Crime Officer

Rigor Mortis

A stiffening of the body that occurs about 30 minutes after death and continues for up to 18 hours.

Livor mortis

A coloration of the skin of the lower parts of a corpse caused by the settling of the red blood cells as the blood ceases to circulate

Algor Mortis

The postmortem cooling of the body.

Ninhydrin

Reagent that turns latent fingerprints purple

Pattern evidence

Evidence in which the shape or distribution of a substance provides information rather than the substance itself.

Gunshot residue

Unburned primer powder sprayed on to the hands of someone firing a gun, and possibly on to the target

Ligature

A cordlike object used for strangulation

Skeletalization

The process of a body's soft tissues completely decomposing to leave only the bones.

Staged crime scene

A crime scene where the perpetrator has left false clues to mislead investigators

Trauma

A wound or a physical or emotional shock to the body

Witness of fact

A member of the general public who testifies at a trial

Manner of Death

Legal classification of how someone died determined by the coroner. Suicide, natural, accidental, or homicide

Accelerant

Fuel used to make a deliberately set fire burn more vigorously

Cause of death

The action that resulted in death, a blow to the head or brain hemorrhage

Class Evidence

Evidence that is specific enough to identify overall characteristics but too general for a unique identification