3. Nature of evidence

Testimonial Evidence

a statement made under oath; also known as direct evidence

Physical Evidence

any object or material that is relevant in a crime; also known as indirect evidence. Examples are hair, fiber, fingerprints, documents, blood, soil, drugs, tool marks, impressions, glass

Transient Evidence

temporary; easily changed or lost; usually observed by the first officer at the scene ex. Oder, Temperature, imprints(footprints, teeth marks, etc.), and markings

Pattern Evidence

produced by direct contact between a person and an object or between two objects ex.Clothing or article distribution, Gun powder residue, Material damage, Body position, Tool marks

Conditional Evidence

produced by a specific event or action; important in crime scene reconstruction and in determining the set of circumstances or sequence within a particular event, Ex. light, smoke, fire, Location, Vehicles, body, scene.

Transfer Evidence

produced by contact between person(s) or object(s), or between person(s) and person(s)

Associative Evidence

items that may associate a victim or suspect with a scene or each other; ie, personal belongings

Biological evidence

blood, semen, saliva, sweat, tears, hair, bone, tissues, etc.

Chemical Evidence

fibers, glass, soil, gunpowder, metal, mineral, narcotics, drugs, etc

Physical Evidence

fingerprints, footprints, shoe prints, handwriting, firearms, tire marks, tool marks, typewriting

Miscellaneous

laundry marks, voice analysis, polygraph, photography, stress evaluation

Class Evidence

common to a group of objects or persons ex. jeans or a piece of hair.

Individual

can be identified with a particular person or a single source, Fingerprints, DNA, Tire marks

General steps of CSI

Recognition, preservation, identification, comparison, individualization, interpretation and reconstruction

Recognition

The first step of CSI, its the ability to distinguish important evidence from unrelated material

Preservation

The second step of CSI collection and proper preservation of evidence

Identification

the third step of CSI, its the use of scientific testing (such as Physical properties ,Chemical properties Etc.)

Comparison

The fourth step of CSI, class characteristics are measured against those of known standards or controls; for example if all measurements are equal, then the two samples may be considered to have come from the same source or origin.

Individualization

The fifth step of CSI, its when demonstrating that the sample is unique, even among members of the same class

Interpretation

The sixth step of CSI, it gives meaning to all the information

Reconstruction

The final step of CSI, its when we reconstructs the events of the case and prepare the report which will be presented in court

nn

A process used in forensic science to establish a connection between evidence and a specific individual or event.