CST Evidence Export & Timestamping 2

Question 1

When exporting video evidence for court, which file attribute is most critical to preserve to demonstrate the footage has not been altered?

Accepted Answer

Cryptographic hash value (MD5/SHA)

Answer

A cryptographic hash value (MD5 or SHA) provides a verifiable fingerprint proving the exported file is bit-for-bit identical to the original.

Question 2

A DVR's internal clock drifts 4 minutes fast over a month. When exporting footage for an incident that occurred at 2:15 PM, what timestamp should be noted in the chain of custody?

Accepted Answer

2:11 PM after subtracting the clock drift

Answer

The corrected time (2:11 PM) should be documented alongside the displayed DVR time, with the clock discrepancy noted in the chain of custody.

Question 3

Which export method best preserves original video evidence integrity compared to screen-capture recording?

Accepted Answer

Native format export directly from the DVR/NVR

Answer

Native format export preserves the original encoded data without recompression or quality loss, maintaining evidentiary integrity.

Question 4

An investigator needs to verify the NVR system clock is accurate before exporting evidence. What is the most reliable reference source for time verification?

Accepted Answer

An NTP-synchronized server or GPS time source

Answer

NTP-synchronized or GPS time sources provide authoritative, traceable time references accepted as accurate in legal proceedings.

Question 5

What document must accompany exported video evidence to maintain admissibility throughout its custody lifecycle?

Accepted Answer

A chain of custody form signed by each person who handled the evidence

Answer

A chain of custody form documents every transfer and handling of evidence, establishing an unbroken record required for court admissibility.

(CST) Certified Surveillance Technician Practice Test

(CST) Certified Surveillance Technician Practice Test

CST Evidence Export & Timestamping 2