Insights · Time

The daylight saving time trap in timestamped footage

December 2024 · 3 minute read

Twice a year the clocks move, and a surprising number of cameras simply do not move with them.

Daylight saving time is one of the most common reasons a camera's clock ends up wrong. A device installed and set correctly in winter can be an hour off all summer, and the people relying on its footage rarely notice until a timestamp is questioned. It is part of why a widely cited FBI training finding holds that more than half of all security-camera systems display the wrong time.

Why an hour can decide a case

In a dispute about sequence, who arrived first, when a fall happened, whether a driver had time to stop, an hour is enormous. Footage stamped in the wrong offset can appear to contradict the truth, and a timeline built on it can collapse under cross-examination.

The defense against the trap is to stop trusting the printed overlay and instead derive the time from the file's own capture metadata, interpreted in the correct local time zone. That is the difference between a timestamp that survives scrutiny and one that invites it.