Intro To CRJ First quiz 31.08.26

Criminal Investigation

A systematic process of identifying, collecting, preserving, and evaluating information and evidence to determine whether a crime was committed, identify the perpetrator, and assist in prosecution.

Patrol Officer

The first responder to a crime scene whose initial observations, scene securing, and preliminary reporting lay the foundation for the entire investigation.

Reactive Investigation

An investigation initiated after a crime has occurred and been reported to law enforcement.

Proactive Investigation

An investigation initiated by police prior to or during criminal activity, often utilizing surveillance or sting operations.

Fingerprinting

The identification technique relying on unique friction ridge patterns on human fingers, serving as a primary means of personal identification in criminalistics.

Anthropometry (Bertillonage)

An early system of personal identification based on precise body measurements, later replaced by fingerprinting.

Modern Investigator

A law enforcement specialist tasked with conducting detailed follow-up investigations, interviewing witnesses, interrogating suspects, and preparing cases for court.

Rand Corporation Study

A landmark 1970s study on police investigative practices showing that patrol officers, rather than detectives, solve a majority of crimes and that traditional investigative work often lacked efficiency.

Case Screening

A management tool used to evaluate reported crimes based on solvability factors to determine whether a case should be assigned for follow-up investigation or suspended.

Solvability Factors

Key elements of information (e.g., named suspect, witness, usable evidence) that indicate a case has a realistic likelihood of being solved.

Preliminary Investigation

The initial phase of an investigation conducted immediately after a crime, usually led by patrol officers to secure the scene, locate witnesses, and gather immediate facts.

Follow-Up Investigation

The secondary phase of an investigation, typically assigned to detectives, which builds on preliminary findings through detailed interviewing, analysis, and tracking of leads.

Compstat

A computer-driven management accountability system that utilizes data, mapping, and regular strategy meetings to address crime patterns and deploy resources effectively.

Crime Analysis

The quantitative and qualitative study of crime patterns, trends, and suspect profiles to assist operational units.

Crime Mapping

The spatial analysis of criminal activity using Geographic Information Systems (GIS) to visualize hot spots and geographic patterns.

Specialized Units

Dedicated investigative squads (e.g., Homicide, Special Victims, Narcotics) focused on specific, complex criminal areas.

Arrest

Taking a person into legal custody to answer to a criminal charge based on probable cause.

Probable Cause

A reasonable belief, based on trustworthy facts and circumstances, that a crime has been committed and that the specific suspect committed it.

Reasonable Suspicion

An objective standard of justification that is less than probable cause but more than a hunch, allowing officers to briefly detain and frisk a person.

Search Warrant

A written order issued by a neutral magistrate authorizing law enforcement officers to search a specific location for specified evidence.

Exclusionary Rule

A constitutional rule establishing that evidence obtained in violation of the Fourth Amendment is inadmissible in court.

Fruit of the Poisonous Tree Doctrine

A legal principle barring secondary evidence that was derived from an initial illegal search, seizure, or interrogation.

Plain View Doctrine

An exception to the warrant requirement allowing officers to seize evidence without a warrant if they are lawfully present and the item's contraband nature is immediately apparent.

Exigent Circumstances

Emergency situations demanding immediate action by police—such as preventing destruction of evidence or hot pursuit—that justify warrantless entry.

Search Incident to Arrest (SILA)

An exception allowing officers to search an arrestee's person and immediate grab area without a warrant to preserve evidence and protect officer safety.

Terry Stop and Frisk

A temporary detention and protective outer-garment pat-down for weapons based on reasonable suspicion that a crime is afoot and the suspect is armed.

Direct Evidence

Evidence that directly proves a fact without requiring any inference or presumption (e.g., eyewitness testimony seeing the crime take place).

Indirect Evidence (Circumstantial Evidence)

Evidence that proves a set of facts from which a jury may infer the existence of another fact (e.g., fingerprints at a scene or possession of recently stolen goods).

Real Evidence (Physical Evidence)

Tangible physical objects related to the crime (e.g., weapons, blood samples, illicit drugs).

Demonstrative Evidence

Charts, diagrams, maps, or models used to illustrate or explain testimony to a judge or jury.

Testimonial Evidence

Oral or written statements provided under oath by witnesses, victims, or suspects.

Admissibility of Evidence

The legal standard governing whether evidence may be introduced and considered by the trier of fact in a court proceeding.

Lineup

An identification procedure where a witness views a live group of individuals to identify a suspect.

Photo Array

An identification procedure where a series of photographs is presented to a witness or victim to identify a perpetrator.

Miranda Warning

A required constitutional warning regarding Fifth and Sixth Amendment rights given to a suspect prior to custodial interrogation.

Custodial Interrogation

Questioning initiated by law enforcement officers after a person has been taken into custody or otherwise deprived of freedom of action in any significant way.

Importance of Evidence

Proves whether a crime occurred, identifies the perpetrator, and connects the suspect to the crime scene or victim.

Proof Beyond a Reasonable Doubt

The high legal burden of proof required to convict someone in a criminal trial, meaning there is no logical doubt of guilt.

Preponderance of Evidence

The lower burden of proof used in civil cases, meaning a claim is more likely true than not (more than 50% chance).

Admission

An acknowledgment of a specific fact or detail related to a crime without admitting full guilt.

Confession

A complete statement admitting full guilt and responsibility for committing a crime.

Why Investigations Cannot Use Excessive Force on Detainees

Violates constitutional rights,( 8th Amendment) renders any confession inadmissible in court, and destroys the legal integrity of the case.