Foundational Concepts & Principles Flashcards

When documenting tire track evidence at an outdoor scene, which environmental factor most urgently dictates the photography timeline?

Answer: Changing weather conditions such as wind, rain, or direct sunlight that can degrade the impression

Environmental conditions such as rain, wind, or direct sun can rapidly destroy impression evidence, making immediate documentation the top priority.

What is the key difference between a forensic photograph and a surveillance photograph?

Answer: Forensic photographs are taken in a controlled, documented process to serve as legal evidence; surveillance photographs are taken covertly to monitor activity

Forensic photographs follow strict protocols for evidentiary documentation, while surveillance photographs are taken covertly to observe ongoing activity without the subject's knowledge.

A forensic photographer is asked to testify as an expert witness. Which qualification is most critical for establishing their credibility?

Answer: Documented training, certifications (such as CFP), and a verifiable record of professional experience

Expert credibility is established through documented education, recognized certifications like the CFP, and a verifiable professional track record.

Which photographic technique is most useful for revealing latent fingerprints on multi-colored or patterned surfaces without chemical processing?

Answer: Alternative light source (ALS) or forensic light source photography using appropriate wavelengths and barrier filters

Alternative light sources can cause latent print residues to fluoresce, making them visible against complex backgrounds when viewed through appropriate barrier filters.

In photogrammetry used in forensic scene documentation, what is the primary purpose of placing coded targets or control points at the scene?

Answer: To provide fixed reference points that allow software to accurately calculate real-world dimensions and create scaled 3D models

Coded targets and control points with known coordinates allow photogrammetry software to establish ground truth measurements and produce dimensionally accurate 3D models.

What is the forensic significance of photographing the negative (or surrounding) space at a crime scene, not only the evidence itself?

Answer: Negative space photography can reveal patterns of absence, such as areas wiped clean, objects removed, or disturbances, that indicate activity

Documenting negative space can reveal critical investigative information such as transfer patterns, void areas in bloodstain, or evidence of cleanup activity.

Why should a forensic photographer avoid using a polarizing filter as standard practice for all crime scene photographs?

Answer: A polarizing filter can eliminate glare that is itself forensically significant, such as specular reflection from wet blood or glass

Specular reflections and glare can be evidence of surface condition or substance type; eliminating them with a polarizer may destroy forensically relevant information.