Chapter 24: Legal Aspects of Forensic Science

Rules of Evidence

Rules of Evidence

determine what evidence may be admitted, for what uses, and under what conditions.

Response to the crime scene

It is the policy of many law enforcement agencies to have a forensic scientist, or perhaps several, attend crime scenes whenever there is a homicide suspected or in cases where there may be a high profile or otherwise notorious crime committed.

Analysis of evidence

an on-going job during a criminal investigation process. Forensic scientists will issue reports on their analyzes which are then evaluated by the prosecutor and criminal investigators.

Depositions

a proceeding in which testimony isCourt Testimony given under oath but not in court or before a judge.

Court Testimony

the most effective way to impart highly technical and complicated facts and opinions to the judge or jury. Forensic scientists may also testify at preliminary hearings.

Discovery

process whereby one side in litigation seeks to gather information about testimony and evidence that is in the hands of the other side

Reciprocal discovery

a principle of criminal procedure that requires the defendant to give the prosecution copies of any pretrial statements that a defense witness gave during discovery

Due Process Clause

protects people against outrageous government behavior.

Subpoena

an order issued under the direction of a court commanding the presence of a witness at a specific time and place to give testimony or other evidence

Subpoena Duces Tecum

type of subpoena commands not only the presence of the witness in court but also any documentation or evidence in his or her possession that is material to the case

Real Evidence

is physical; it consists of things that help link a suspect to a crime or explain the circumstances of the incident.

Demonstrative Evidence

which consists of supporting materials such as crime scene photos or sketches.

Testimonial evidence

the oral recitation of facts and sometimes impressions or opinions by a witness under oath

Lay Witnesses

usually limited to first-hand observations and impressions; they are often called upon to state on facts

Expert Witnesses

often called upon to state conclusions and opinions based upon their examination of evidence or observation of the crime scene or parties to the crime

Chain of Custody

both a process and a document that memorializes the transfer of evidence from the custody of one person to another.

Admissibility of Evidence

evidence that may be presented before the trier of fact (i.e., the judge or jury) for them to consider in deciding the case

material

If evidence is _________, it means that it applies to a matter dealing with the case at hand, and not some other case.

probative

Evidence is ________ if it tends to make a fact or issue more or less probable than if the evidence were not present.

Competence

a collection of rules and constraints that evidence must pass muster with in order to be admissible.