All About Evidence

Dairon CaroRobert GarciaDenise Perez

Is any item or information gathered at the scene of a crime, or at related locations which tends to disapprove or establish something.

It can be divided into two general goods:

Testimonial Evidence Physical Evidence

Evidence

Testimonial Evidence

Statement made under oathIt’s said in court by a competent

witness.Also called direct evidence

Important factors to take in account with eye witness

Type of crime & how witness saw it. Memory (ability to remember characteristics. Ex: hair,

color, sex, age height, reliving event, if their was a presence of weapons.)

Interviewing techniques (open ended questions) Relationship of witness to suspect How much time has passed between offense and id. If the witness id the defendant.

***** Most known cases of an innocent person being convicted has happened due to a mistaken eye witness.

The Innocence Project

National Organization dedicated to exonerating wrongfully convicted people through DNA evidence.

Number 1 cause of wrongfully convictions nationwide is because of eye witness misidentification.

Jeffrey Dahmer Case

Physical EvidenceTangible tend to prove or disapprove a factReal evidenceRefers to any item that would be present at

the crime scene on the victims out found in a suspects possession.

more reliable than testimonial evidenceCan be any material or object in any shape,

size, form.

Physical Evidence

Types of Physical Evidence:

Trace Evidence Transient Evidence Conditional Evidence Indirect Evidence Individual Evidence Class Evidence

Trace Evidence refers to physical evidence that is found in

small but measurable amounts. (For example: hair, fibers, skin cells, DNA, blood, etc.)

Transient Evidence temporary evidence can be easily changed

or lost. Recorded at the time by usually the first office at the scene. (For example: odors, temperature, imprints, etc)

Conditional Evidenceproduced by a specific action or event at the

scene. (For example: lights, doors, windows, position of furniture, etc)

Indirect Evidencedoes not prove or disprove a fact in question.

(For example driving under the influence)

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Individual Evidencecan be related to a single source. (For

example fingerprints. Handwritings, etc)

Class EvidenceCan be associated with a group of items that

share properties or characteristics. (For example: blue jeans)

Physical Evidence

The Locard PrincipleLocard's Exchange

Principle states that with contact

between two items, there will

always be an exchange. This is the basis of trace

evidence collection at a crime scene.

“Every contact leaves a trace”

Probability and Class Evidence Activity

Today in school, a student was seen from far vandalizing a hallway in the 3rd building. The person was wearing a black shirt, khaki pants, black shoes and had brown hair. How can we figure out who the student was or how to narrow the pool of suspects?

Packaging Evidence

Activity Time!!!

THE END!