Chapter 3: The Role of Evidence in Criminal Investigations

What are corpus delicti evidence, corroborative evidence, cumulative evidence, association evidence, identification evidence, and behavioral evidence?

Corpus delicti evidence: Evidence that establishes that a crime actually occurred. Ex. Knife in dead body. Corroborative evidence: Evidence that is supplementary to the evidence already available and which strengthens or confirms that available evidence. Ex. Fingerprints of perp. Cumulative evidence: Evidence that duplicates but doe snot necessarily strengthen already existing evidence. Ex. five witnesses of the same event instead of one. Association evidence: Evidence that can be used to make links between crimes, crime scenes, suspects, and tools or instruments. Ex. Dead body associated with odor in car, Casey Anthony case. Identification evidence: Evidence that leads to the identification of the perp. Ex. Fingerprints, DNA, dental records. Behavioral evidence: Provides a basis on which to identify the type of person who may be responsible for a particular crime and considers directly the nature of the crime and how it was committed. Ex. Profiles, offender types.

What is the difference between direct evidence and indirect evidence? Is one type of evidence more useful than the other? What are the various types of circumstantial evidence?

Direct Evidence: Crime-related information that immediately demonstrates the existence of a fact in question. Indirect Evidence: AKA circumstantial evidence, consists of crime-related information in which inferences and probabilities are needed to draw an associated conclusion. It is not that one is better than the other, its that a distinction between the two is needed depending of the inferences to draw and associated conclusion. Types of circumstantial evidence: 1.) Ones physical ability to commit the crime. 2.) An alibi or lack of one, 3.) MO, Modus Operandi, 4.) Existence of an identifiable motive, 5.) Evidence concerning an individuals attempts to avoid apprehension after the crime occurred, 6.) If an individual is found to be in the possession of the fruits of the crime, 7.) The existence of prior threats made by the suspect or similar behaviors prior 8.) Character witnesses can be introduced

What is the difference between exculpatory evidence and inculpatory evidence?

Exculpatory Evidence: Is evident that tends to exclude or eliminate someone from consideration as a suspect. Inculpatory evidence: Evidence that tends to include or incriminate a person as the perp. An example is the lack of an alibi.

What is hearsay? What is the hearsay rule? What are the major exceptions to the hearsay rule?

Hearsay: Hearsay rule: Exceptions to the hearsay rule:

What is the difference between judicial evidence and extrajudicial evidence?

Judicial evidence: AKA admissible evidence, evidence that is allowed in court. Extrajudicial evidence: Evidence that is not admissible, any information on which an investigative decision can be based but which i snot allowed in court. Example is the result of a polygraph.

What are lay witnesses and expert witnesses? What is the role of each in court?

Lay witnesses: Individuals whose testimony is limited to the facts as personally observed. Expert witnesses: People who posses special knowledge about a particular issue or phenomena under examination.

What is proof? What are the various levels or standards of proof?

Proof is to prove something occurred, or, to eliminate uncertainty, or to eliminate to some degree of uncertainty, regarding the truthfulness of the conclusion. Standards of Proof: 1.) Probable Cause: This exists when it is more likely than not that a particular circumstance exists. 2.) Beyond a reasonable doubt: Needed in trial to conclude that a defendant is guilty of the crime. 3.) Reasonable suspicion: In order for police to legally stop and frisk, they need to have reasonable suspicion that a persons involvement or association with a criminal act. 4.) Preponderance of the evidence: Degree of certainty needed to prove and win a civil case

What are the differences between testimonial evidence, real evidence, documentary evidence, and demonstrative evidence?

Testimonial Evidence: Evidence that is presented in court through witnesses speaking under oath when those witnesses would be committing perjury if they did not state what they believed to be true. Real Evidence: AKA physical evidence, scientific evidence, forensic evidence. The tangible objects that can be held or seen and that are produced as a direct result of the commission of a crime. Documentary Evidence: Tangible objects produced indirectly from the crime that relate to the crime or perp. Ex. diagrams, videos, photos. Demonstrative Evidence: Refers to any evidence that is in the form of a document or to evidence that documents some issue related to the crime.