Investigation & Evidence Flashcards
7 cards from real CPD practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Investigation & Evidence flashcards as text
What is the correct order of steps when collecting physical evidence at a crime scene?
Answer: Document, photograph, collect, package, and label
Proper evidence handling requires documentation and photography before any item is collected, then packaging and labeling for chain of custody.
A confidential informant provides a tip that a specific apartment contains illegal weapons. To obtain a search warrant, the officer must demonstrate:
Answer: The informant's reliability and basis of knowledge, establishing probable cause
Under the Illinois v. Gates totality-of-circumstances test, the informant's track record and how they know what they claim to know must support probable cause.
Which interview technique involves allowing a witness to narrate events in their own words without interruption before asking clarifying questions?
Answer: Cognitive interview technique
The cognitive interview encourages free recall narrative first, which produces more accurate and complete information from witnesses.
A suspect is arrested and invokes their right to counsel. Investigators must:
Answer: Immediately cease questioning and not resume until counsel is present
Invoking the right to counsel requires all questioning to stop until an attorney is present, per Edwards v. Arizona.
Trace evidence such as hair, fiber, and glass fragments is governed by Locard's Exchange Principle, which states:
Answer: Every contact between a person and a place leaves a mutual transfer of material
Locard's principle holds that whenever two objects come into contact, they exchange material, making trace evidence forensically valuable.
An officer prepares a case report for a robbery investigation. The report should contain:
Answer: Factual observations, witness statements, evidence collected, and all investigative steps taken
Investigative reports must be objective, factual, and comprehensive, documenting all observations and actions without editorial opinion.
Under Illinois law, how long may police generally detain a suspect for investigation before charges must be filed or the suspect released?
Answer: 48 hours, with judicial approval required to extend detention
Illinois law generally requires that a detainee be brought before a judge within 48 hours; detention beyond that requires judicial authorization.