CCTV & Surveillance

How to Preserve CCTV Evidence for Police Prosecution

8 min read· Updated 2026-07-07· Free · No signup

Evidential CCTV is only useful if it survives the chain-of-custody test in court. Sloppy extraction, missing timestamps, or amateur editing can render damning footage inadmissible.

Key takeaways

Original file preservation before any copy or export.
Timestamp accuracy verified.
Chain of custody documented from extraction to handover.
Never enhance or crop before police receipt.

The moment an incident happens

Note the exact time on every camera involved. Lock the footage in the DVR/NVR from being overwritten. Do not export yet — police may bring their own extraction tools.

Extraction done properly

Use manufacturer-native format. Include hash values where the system supports it. Log extractor name, time, and reason.

Handover

Signed handover form. Receiver's warrant/collar number. Copy retained by site, original with police (or vice versa per force policy).

Quick checklist

Time lock applied immediately
Native format extraction
Chain of custody signed
Nothing enhanced or edited pre-handover

Common mistakes

Screen-recording with a phone.
Compressing before handover.

Frequently asked questions

How long should I keep CCTV?+

As long as necessary for the stated purpose. Most sites default to 30 days; longer requires justification.

Can I give footage to a customer?+

Only via Subject Access Request or with legal basis. Refer to your DPO.

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