CSI TEST #1

Edmond Locard

He postulated that when someone enters into an environment, something is added to and/or something is removed. When two objects come in contact with one another, there will be a cross transfer of evidence. This applies to contact between individuals as well as between individuals and the environment.

What is CSI

involves the location, documentation, collection, protection and analysis of physical evidence of a crime

Preliminary Investigation

responding officers first receive the call. It continues through the writing and filing of the primary officer’s investigative report.

This investigative proces includes

• victims

• witnesses

• CSI

• Medical examiners

Role of Responding Officers

to secure and protect the integrity of the crime scene until officially and properly relieved. Initially, police officers should not touch anything or do anything that could alter a crime scene in any way except to preserve life or administer aid to a victim

Contamination

When two objects touch each other, it is possible for trace substances of one to be transferred to the other.

Protecting the Crime Scene

• establish a perimeter

• maintain crime scene log

• evidence protection

• place fixed barriers

inner perimeter (donut hole)

area which contains specific evidence of the crime.

Outer perimeter (donut)

established as a means of securing and controlling access to the inner perimeter

Perishable

• fingerprints

• hair and fiber

• paint chips

Chain of Custody

The written, witnessed, unbroken record of all individuals who maintained control or had access to any physical evidence. A complete and accurate chain of custody record is absolutely essential in establishing the validity and integrity of evidence in court.

Field Evidence Technician

someone who generally handles routine crime scenes through photography, sketching, evidence collection and latent fingerprint processing

Respond Calls

• Homicide

• Shootings

• Burglaries

Cornor

A public official who investigates by inquest any death not due to natural causes

Trace Evidence

Any evidence that is very small; it usually cannot be seen with the naked eye without close scrutiny

Basic Finger Types

• Loops - 60

• Whorls - 35

• Arches - 5

Fingerprints are composed of 98.5 % to 99.5% water

The balance of organic and inorganic components that you secrete

Oils found on fingers come from other parts of the body that the hands touch.

Plastic Prints

Fingerprint indications left on clay or wax

Latent Print

Hidden prints that only become visible when using fingerprint powder

Patent Prints

Visible prints

DNA

A substance found in the chromosomes in the nucleus of human cells that provides genetic coding information unique to every person