Submitting video evidence to police: what to hand over and in what format
You filmed the incident as it happened and you assume the footage speaks for itself. Then you send it to a relative through a chat app, copy it onto a memory stick and walk into a police station. Submitting video evidence to police is not a neutral act: between the recording and the counter the file changes technical identity more than once, and every step takes away something nobody can put back. The officer at the desk is not judging your images, they are registering a digital object and writing down what it is.
Submitting video evidence to police means handing over the file exactly as the recording device generated it, on dedicated media or through an official upload channel, with the data documenting its origin: device, date, time, location, size in bytes and hash. Not a copy pulled out of a chat thread. ISO/IEC 27037, the international standard for handling digital evidence, turns on a point anyone can check: the holder must be able to show the file did not change before the handover.
This insight is part of our guide: How to certify a smartphone video as legal evidence in court
The video you hand over is no longer the video you recorded
Footage that reaches a counter almost always has a technical history behind it: shared with someone, re-encoded on the way out. What makes a recording admissible is the subject of the parent guide on the evidential value of a smartphone video. The question here comes earlier: what is left inside the file by the time you hand it over.
What gets stripped between the recording and the drive
A video shared through a messaging app is not a copy of the original video file. It is a new file. The service re-encodes it to cut its weight, changes codec and container, lowers bitrate and resolution, renames it and strips the technical data it carried. The device clock date and time disappear, along with the capture coordinates, the phone model and the orientation. Those are the metadata that place a photo or a video in time and space, and NIST's computer forensics tool testing programme shows how much of it depends on the way data is pulled off a handset. On screen the files look identical; as a record of origin, the second is mute.
How the defence attacks a video file
A video file gets challenged on two fronts, both procedural rather than visual. The first: what was handed over is not the original video file, because nothing ties the drive to the file born in the phone's memory. The second: there is no way to prove when and where it was recorded, because the internal time reference is gone, or it is a device clock anyone can reset before pressing record.
Neither is answered by playing the video again. Both are answered with documentation: the chain of custody of digital evidence, the traceable history of the file from capture to handover, the ground covered by the ground covered by the NIJ guide for law enforcement and NIST's forensic science programme. TrueScreen, the Data Authenticity Platform, computes the file hash and binds a certified time reference at capture, before the recording can be shared or re-encoded.
How to hand a recording to the police
Where you hand a recording over depends on the country. UK forces collect dash cam and citizen footage through upload portals under Operation Snap, and several US agencies run something similar; across much of continental Europe the file is delivered in person, at the counter where the report is taken. The procedure varies. What travels with the file does not.
Media, format and accompanying data
The handover comes down to three moves: preserving the original file without touching it, delivering it on media the receiving office can keep, and getting what was delivered written down. The first is where most people fail, because it happens before you leave the house: the file must be copied off the device memory via a computer, not retrieved from a conversation. The second means dedicated physical media, since nobody at the counter wants your phone. The third depends on you asking, because it is office practice rather than a printed rule. The US Bureau of Justice Assistance guide on video evidence for law enforcement treats the file and its accompanying data as one package.
| Item | What to hand over | Common mistake |
|---|---|---|
| Media | A new USB drive or disk, dedicated to that case | Handing over the phone, or a drive already used for other things |
| File | The native file copied from the device memory | Attaching the copy downloaded from a chat |
| Format | The source format, with no re-export and no compression | Converting the video so it plays everywhere |
| Hash | The value computed before the handover, supplied in writing | Handing over the media with no integrity reference |
| Capture data | Device, date, time, time zone, location, duration, author | Relying on memory once you are standing at the counter |
| Retained copy | An identical copy kept by the person reporting | Handing over the only existing copy |
Six things go with a recording when you submit it:
- The original file, copied from the recording device and never re-exported.
- New digital media, a USB drive or disk, dedicated to that case.
- The hash of the file, computed before you reach the counter.
- Make, model and identifier of the device that recorded the footage.
- Date, time, time zone, location and duration of the recording.
- An identical retained copy carrying the same hash value.
Then ask for the details to be recorded: the handover record, or the receipt an upload portal generates, should carry the exact file name, the size in bytes, the hash value and the type of media. Four lines that let anyone check, months later, whether the file on the case system is still the one submitted. Portals also cap file size, which is why physical media remains the fallback.
What not to do:
- Send the footage through a chat before copying it off the device.
- Trim, rotate or edit the recording to make it easier to follow.
- Upload the video to cloud storage and download it again to copy it.
- Post the images on social media before the report has been filed.
- Delete the file from the phone once the media has been handed over.
Street property damage and repeated harassment
A car mirror snapped off in the street produces the simplest kind of recording: forty seconds shot on instinct, often with a bystander watching. The handover is linear: phone connected to a computer, file copied directly, hash computed, drive prepared, and the bystander's details in the report next to the capture data. The same applies to third party footage, a shop camera for example, where admissibility of video gathered outside a formal investigation depends on how cleanly the file was obtained.
Repeated harassment works differently. One clip says very little; the chronology says almost everything, because it is the pattern of documented episodes over time that describes the conduct. So you hand over a single drive, files named by date, an index ordering them, and a hash for each.
What changes when the video is certified as it is recorded
Individuals and organisations use TrueScreen to record footage that arrives at the counter already carrying its own hash, time reference and acquisition data. Certifying later attests that a file existed on a given date. Capturing at source documents the act of recording too, with the time fixed by a qualified timestamp issued by a QTSP integrated into the platform. Both lines of attack lose their footing, because what is needed to test them travels with the file.
Recording with the TrueScreen app removes the export step that strips a video of its technical data. Two days later, at the counter, you produce the native file with hash and time reference already computed, and the officer copies them into the record without rebuilding anything. The same applies when you certify a video for an insurer rather than the police.
