Ch 3. The Crime Scene

Accelerant

A flammable substance used to help start a fire

Individualized Evidence

A kind of evidence that identifies a particular person or thing

Circumstantial evidence

(Indirect evidence) Evidence used to imply a fact but not prove it directly

Ultraviolet lighting

A black light used to make phosphorescent and fluorescent paints glow in the dark.

Inference

A conclusion reached on the basis of evidence and reasoning

Crime Scene Investigation

A multi-disciplinary approach in which scientific and legal professionals work together to solve a crime

Medical Examiner

A physician who performs an autopsy when death may be accidental or violent. He or she may also serve in some jurisdictions as the coroner.

Chain Of Custody

A written record of all people who have had possession of an item of evidence

Indirect Evidence

Evidence providing only a basis for inference about the disputed fact

Direct Evidence

Evidence that (if true) proves an alleged fact, such as an eyewitness account of a crime

OJ Simpson Murder Case

Example of beyond a reasonable doubt (not guilty) and preponderance of the evidence (guilty)

Controls

Experimental conditions that remain constant

Corpus Delicti

Facts proving that a crime has been committed; body of the victim in a murder case

Collection Of Wet Materials

First are dried before packing to prevent mold/mildew

Wheel Or Spiral Method

Investigator(s) examine the area for evidence in an ever-widening circle, from the position of the core crime scene or on the perimeter and then moves in an outward direction.

Grid Method

Is best used in large crime scenes such as fields or woods. Several searchers, or a line of them, move alongside each other from one end of the area to be searched to the other.

Class Evidence

Material that can be associated only with a group of items that share properties or characteristics

Modus Operandi

Method of operating, the usual way

Qualitative

Relating to, measuring, or measured by the quality of something rather than its quantity.

Quantitative

Relating to, measuring, or measured by the quantity of something rather than its quality.

Crime Scene Legend

Serves as a graphic document to shows the layout, orientation and interrelationships of the scene and evidence. It supports the final report and allows viewers to quickly understand the scene set-up.

Oblique lighting

Sweeping a flashlight beam back and forth over a hard surface in a semi-dark indoor area. This light can show items that are not visible in normal light.

Physical Evidence

Tangible items that tend to prove some material fact; also called real evidence

Crime Scene Key

Tells you what evidence matches with the numbers at a crime scene analysis.

Observation

The action or process of observing something or someone carefully or in order to gain information.

C.S.I. Effect

The influence that crime shows such as C.S.I. have on the public's perception of forensic science.

Crime Scene

The location where a crime has been committed or any place that evidence relating to a crime may be found.

Crime Scene Reconstruction

The method used to support a likely sequence of events at a crime scene by the observation and evaluation of physical evidence and statements made by individuals involved with the incident.

Zone method

Used on crime scenes that are comprised of readily definable zones, such as in houses or buildings. Teams are assigned small zones for searching, and then other appropriate searching methods are employed in each zone.

Line Method

Used on large, outdoor crime scenes. Members of the search team are arranged at regular intervals, usually arm's length, and then proceed to search along straight lines.

Testimonial Evidence

What is said in court by a competent witness; also called direct evidence

Locard Principle

Whenever two objects come into contact with each other, there is always a transfer of material