Giving CCTV footage to the policehow to export it so it still counts as evidence

Plenty of recorders can write-protect a selected sequence so the loop skips over it. If yours can, use it immediately, before you start working out cables and USB sticks. It costs seconds and it takes the clock pressure off.

The police guidance is blunt about the caveat, though: it should not be assumed that this facility will be present. Some systems have no such feature at all. Check rather than trust, and if there is no lock, treat the export as urgent.

One related trap. Do not stop the recording in order to do the export. The guidance says recording should not be stopped during retrieval unless the system forces it, or unless data is about to be overwritten before it can be retrieved. Stopping the recorder to protect one clip while an incident is still unfolding creates a fresh gap in the record.

It is the most common thing people do, and the guidance names it directly. Recording the screen using body-worn video devices or camera phones is described as poor practice, because it does not capture the original data. The result is a significant drop in image quality that compromises the value of the imagery and makes further analysis difficult or impossible. It is to be used as a last resort only, where every other option has been exhausted or there is an immediate risk of harm.

Think about what gets destroyed. A phone pointed at a monitor records a re-photographed image with the screen's own refresh, glare and colour shift baked in, at whatever angle you were standing. Any chance of enhancing a number plate or a face out of the original data is gone, because you never had the original data.

The same logic applies to converting a file after export. Guidance quoted in the recovery document says media where original data has been converted to a different format should be clearly marked as converted format, and is therefore no longer a true copy of the original. Before you make any copy that is not identical to the original, it suggests three questions: will the resulting drop in quality still yield a usable image, will any associated metadata be retained, and will any associated audio be retained.

If a phone recording genuinely is the only thing standing between the police and nothing at all, do it. Just say clearly what it is when you hand it over, so nobody treats it as the original.

Almost nobody does this, and it is the error most likely to weaken otherwise good footage. Recorder clocks drift. They also get left on the wrong side of a clock change.

The guidance asks for a time check: compare the time displayed by the CCTV system with a reliable, accurate time source, record any discrepancy, and compensate for it during retrieval. It notes this is critical where footage from several separate systems has to be compared or synchronised, which is exactly what happens when police pull clips from a row of houses or a street of shops.

The reason it matters is worth understanding, because it is not about picture quality. Guidance distinguishes integrity from authenticity: adjusting brightness or contrast affects the integrity of an image but not its authenticity, whereas an inaccurate clock affects authenticity without touching integrity. Authenticity is the question of whether the footage is what it claims to be, including whether it was taken when it says it was. A perfectly sharp clip timestamped forty minutes out invites exactly the wrong question in court.

So: check it, note the difference in writing, and hand that note over with the file. Do not quietly fix the clock and re-export, because then your copy no longer matches what the system recorded. On networked and IP systems, take extra care, since these may reference more than one time clock.

It is also a standing requirement of a well-set-up system rather than an afterthought. The police requirements say the system clock should be set correctly and maintained, taking account of GMT and BST, and note that incorrect time and date information drains police time and resources. The time and date should be legible and integral to the exported picture.

People hesitate here, and the hesitation costs footage. Handing material to the police is a recognised reason to disclose it, and holding back could get in the way of an investigation.

Whether data protection law applies to your system at all turns on where the cameras point. The Information Commissioner's Office position is that the rules engage once a domestic camera captures someone else's property, a public area or a communal space. A camera seeing only your own garden sits outside that. A doorbell camera watching the pavement does not.

The risk is not in giving footage to the police. It is in what happens next. Posting the same clip on social media or circulating it round a neighbourhood group is onward disclosure, and that is where householders get themselves into difficulty. Give it to the investigating officer and leave it there.

One caveat on timing: the ICO's CCTV guidance currently carries a notice saying it is under review following the Data (Use and Access) Act 2025, so treat the detail as the current position rather than a settled one, and check the ICO directly if a lot turns on it. If you are on the other side of this and want footage that somebody else holds, that is a different process entirely, covered in our guide to requesting CCTV footage from a business or a neighbour.