Forensic Image Metadata & Authentication Flashcards

To be admissible in a U.S. court, a forensic photograph must satisfy what foundational evidentiary requirement?

Answer: It must be authenticated as a fair and accurate representation of what it depicts

U.S. courts require that photographic evidence be authenticated — typically through witness testimony — as a fair and accurate representation of the subject matter at the relevant time.

What does a 'trusted timestamp' from a Time Stamping Authority (TSA) provide for a forensic photograph?

Answer: Cryptographically verifiable proof of when the image existed in a specific unaltered state

A trusted timestamp from a TSA cryptographically certifies the exact time a specific version of a file existed, providing tamper-evident, third-party-verified time documentation.

What is steganography, and why is it relevant to forensic image analysis?

Answer: The practice of hiding data within image files, relevant for detecting concealed information

Steganography is the concealment of hidden data within digital files such as images; forensic analysts may need to detect messages or evidence covertly embedded in images by suspects.

What action should be taken if the recomputed hash value of a forensic photograph does not match the original recorded hash?

Answer: Treat the image as potentially compromised and investigate the source of the discrepancy

A hash mismatch indicates the file has been altered or corrupted; the image must be flagged as potentially compromised and the discrepancy fully investigated before it can be used as evidence.

Which color space is most appropriate for forensic photography when scientifically accurate and reproducible color representation is required?

Answer: A calibrated wide-gamut color space such as Adobe RGB (1998) matched to output devices

Adobe RGB or another calibrated wide-gamut color space preserves more color data than sRGB and, when paired with device calibration, ensures color accuracy is reproducible across different display and print systems.

What role does a forensic shot log (image log) play in supporting the authentication of forensic photographs?

Answer: It provides a systematic written record of each photograph's subject, sequence, time, and capture conditions

A shot log documents each photograph's content, sequential number, capture time, lighting conditions, and camera settings, providing context and written accountability that supports authentication in court.

Under the Federal Rules of Evidence, which rule primarily governs the authentication of photographs offered as evidence in U.S. federal court?

Answer: FRE 901, which requires authentication or identification of evidence

FRE 901 requires that evidence be authenticated by producing sufficient evidence that the item is what the proponent claims; this is the primary rule applied when introducing photographs into evidence.