Chapter 2: Physical Evidence in the Legal System

Striations

result of a hard surface common in contact with an object in motion (tool) creating an individual marking along the surface

Cold case

an unsolved criminal investigation which remains open pending the discovery of new evidence

Daubert Evidence Rule

provides systematic framework for a trail court judge to assess the reliability of& relevance of expert witness testimony before it is presented to a jury

Deposit

a substance, material, or trace left behind on a person, object, or surface that can be collected & analyzed as evidence, such as the transfer of fibers, hairs, blood, or DNA

Exclusion

a test result that indicates a known individual’s genetic or other biological profile is not the source of the evidence found at a crime scene or on a victim

Expert Witness

a person with specialized knowledge, training, or experience who testifies in court to offer opinions on scientific or technical matters to help a judge or jury understand evidence or complex issues in a case

Frye Evidence Rule

the court must determine that the scientific evidence is “generally accepted” by a significant portion of the relevant scientific community in order for it to satisfy the Frye standard

Known (K)

a sample of known composition, source, or type that is used for comparison with unknown evidence (often labeled as “Q” for question) collected at a crime scene

Probable Cause

the legal standard requiring sufficient facts & circumstances for a reasonable person to believe that a crime has been, is being, or will be committed, & that a search will find evidence of that crime or that specific person committed it

Questioned (Q)

a document, sample, or item whose authenticity, origin, or validity is disputed in legal context & requires examination to determine the facts

Trier of Facts

the person of a group (like a judge or jury) responsible for evaluating all evidence, including forensic evidence, & determining the facts of a legal case to reach a verdict