forensics

crime scene:

Any physical location in which a crime has occurred or is suspected of having occurred

primary crime scene:

The original location of a crime or accident

secondary crime scene:

An alternate location where additional evidence may be found

suspect:

Person thought to be capable of committing a crime

accomplice:

Person associated with someone suspected of committing a crime

alibi:

Statement of where a suspect was at the time of a crime

eyewitness statement:

Refers to an account given by people of an event they have witnessed

testimonial evidence:

Includes oral or written statements given to police as well as court testimony by people who witnessed an event

trace evidence:

Fragments of physical evidence that can be transferred when two objects interact

physical evidence:

Refers to any material items that would be present at the crime scene, on the victims, or found in suspects possession

secure the scene -

done by first responding officer

seperate the witnesses -

ensure that no one present at the scene of the crime communicates with each other

scan the scene -

determine what to photograph

seeing the scene -

take photographs

sketch the scene -

a rough sketch of the scene before the final copy is created

search for evidence -

take a linear, spiral, grid, or quadrant route in order to locate evidence

secure the evidence -

ensure all collected evidence is properly packaged and sealed

who is part of the investigation team?

·       Police officers

·       Crime scene investigators

·       Medical examiners

·       Detectives

·       Forensics specialists

·       District attorney (if required)

eyewitness example

Eyewitnesses may be required to give description at a trial of a robbery or a road accident someone has seen. This includes identification of perpetrators, details of the crime scene, etc.

reality for eyewitnesses

**In reality**, the memory doesn’t record experiences (like a video camera); It creates stories based on true experiences

physical evidence examples?

paint, glass, explosives, ballistics, dust/dirt, tracks, fingerprints, tool marks, wounds, dna, skeletal remains, bodily fluids

what are the different types of evidence?

circumstantial (ie. trace), physical, biological, testimonial, class/individual

what is the chain of custody?

the movement + location of physical evidence from the time it is obtained until it is presented in court

what are the different priorities at a crime scene?

·       Obtain medical aid to those in need

·       Arrest the perpetrator

·       Secure the crime scene

·       Determine crime scene boundaries

·       Located path of entry and exit

what happens when lead investigators arrive at the scene?

1\.     Boundaries of scene determined

2\.     Establish perpetrators path of entry and exit

3\.     Obvious items photographed and documents

4\.     Initial walk through to gain overview and develop strategy for systematic search

what are fibres?

smallest unit of textile material woven or twisted together to form a thread or yarn

what are the types of fabric weaves?

plain, twill, and satin

what are types of synthetic fibres?

polyester, rayon, nylon, acetate, acrylic, spandex

what are types of natural fibres?

silk, cotton, wool, mohair, cashmere

what is the usage of hair particles?

It can give evidence of age, gender and race which can strengthen ties between a suspect and the crime scene

rigor mortis

the stiffening of the body muscles after death