Forensic Science Principles & Investigative Methods Flashcards
7 cards from real CFC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Forensic Science Principles & Investigative Methods flashcards as text
Which principle states that every contact between two objects leaves a trace that can be detected?
Answer: Locard's Exchange Principle
Locard's Exchange Principle holds that any physical contact between two surfaces results in a mutual transfer of material.
What is the primary purpose of establishing a chain of custody for physical evidence?
Answer: To document everyone who handled the evidence and ensure its integrity
Chain of custody documents the chronological history of evidence handling to ensure it has not been tampered with or contaminated.
In forensic investigations, what does 'class evidence' refer to?
Answer: Evidence that can narrow an item to a group but not a single source
Class evidence shares characteristics common to a group of items, such as a shoe print matching a particular brand, but cannot uniquely identify a single source.
What is the correct sequence for processing a crime scene?
Answer: Secure, document, collect, analyze
Crime scenes must first be secured to prevent contamination, then thoroughly documented before any evidence is collected and later analyzed.
Which type of fingerprint pattern is the most common in the general population?
Answer: Loop
Loop patterns account for approximately 60–65% of all fingerprints, making them the most frequently encountered pattern type.
A forensic investigator discovers luminol-reactive stains at a crime scene. What does a positive luminol reaction indicate?
Answer: Possible presence of blood or other peroxidase-containing substances
Luminol reacts with the iron in hemoglobin but can also react with other peroxidases, plant matter, and some cleaning agents, so it is presumptive, not confirmatory.
What is the role of a forensic consultant's expert report in legal proceedings?
Answer: To provide a written summary of findings and opinions that can be used by counsel and the court
An expert report documents the consultant's methodology, findings, and opinions, serving as a foundation for testimony and allowing opposing counsel to prepare cross-examination.