Crj 4220 Chapter 5

latent prints

Are made when oil and perspiration naturally present on fingertips are transferred to another surface but are invisible until developed through techniques

Methods of recovering finger prints

Chemical methods can be used to recover prints from soft porous surfaces such as paper or clothing. Latent prints can be recovered through application of powders, chemicals, and glue fumes.

major types of physical evidence

Class characteristics evidence and individual evidence

5th responsibility of 1st responder

Crime scene must continuously be protected from persons at or near the scene. Authorized personnel and individuals essential to the investigation should be allowed

Touch DNA

DNA from skin cells transferred onto the surface of an object by simple contact

2nd responsibility of 1st responder

Determination has to be made about the legality of entering and searching the crime scene. A search requires a warrant or must be justified by an exception to the requirement.

individual characteristics

Features of physical evidence that allow it to be associated with a particular source.

The responsibilities of the investigator in charge

First, they should establish a crime scene debriefing team. Second, a final survey of the crime scene should be made to make sure the crime scene investigation is complete and no evidence or materials have been left behind. Lastly, the investigator in charge should ensure that all necessary reports and other documentation are completed.

corpus delicti evidence

Helps establish the elements of a crime

epithelial cells

Human tissue cells that cover internal body surfaces and can be used for DNA Analysis

Buccal swab

Involves collecting cells from the inside surfaces of the cheeks

Major Search patterns

Link method, Line method, Grid method, Zone method, Wheel/ray method, and spiral method.

4th responsibility of 1st responder

Next responsibility is to provide or summon necessary medical attention for injured parties

Visible impression prints

Occur when the print is left in a soft or sticky material, such as wet paint, clay, or putty

6th responsibility of 1st responder

Officer must establish the boundaries of the crime scene in order to protect it.

3rd responsibility of 1st responder

Officers need to be constantly mindful of potential threats to their safety, including hazardous materials, chemical threats, and dangerous people.

Gun Residue

Patterns may be found on a victim and used to estimate the distance of the muzzle from the victim.

Why is physical evidence important?

Physical Evidence can prove a crime was committed, that a suspect was at the scene, or establish the identity of persons involved. It could also exonerate the innocent and corroborate witnesses' testimony. A suspect confronted with evidence may confess. Physical evidence does not change, people's stories can/do/will change. Juries expect evidence to be presented. Sometimes, the lack of physical evidence may also provide useful information or direction.

Class characteristics

Properties of evidence that can be associated only with a group and never with a single source.

1st responsibility of 1st responder

Responding officer should be thinking about protecting the scene as well as the safety of himself or herself, other officers, and citizens.

Forensic entomology

The area of forensic science that relates to the study of insects

Forensic Anthropology

The area of forensic science that relates to the study of skeletal remains

7th responsibility of 1st responder

The initial responding officer should brief the investigators taking charge of the investigation.

2nd step in processing a crime scene

The investigator in charge must require that all personnel follow procedures to ensure safety and the integrity of the evidence being documented and collected.

3rd step in processing a crime scene

The investigator in charge should determine which items are to be collected and in what order.

Corroborative evidence

Used to support other evidence in establishing a fact in question

visible transferred prints

When ink, blood, or some other visible liquid material is transferred from the fingertip to another surface

Forensic Pathology

an area of forensic science that relates to the study of dead bodies

1st step in processing a crime scene

determine who is responsible for what and establishing the composition of the investigative team.

Primary classifications of fingerprints

loops, whorls, and arches

minutiae

small or trivial details, trifling matters

Locard's Exchange Principle

states that when a criminal comes in contact with an object or person, a cross-transfer of evidence occurs. " Expect to find evidence".

4th step in processing a crime scene

team members should ensure the proper collection, preservation, packaging, and transportation of evidence.

Forensic Odontology

the application of dentistry to legal matters

identification evidence

used to determine the identity of an individual. can be direct or circumstantial.