Preserve audio & video evidence

Keep the earliest available recording unchanged, together with what you know about where it came from. Make a separate working copy before trimming, converting or enhancing it.

The original recording may still be on a phone, recorder, camera system or account. A file forwarded to your legal team may already have been exported or processed. Record that distinction rather than calling every received file an untouched original.

1. Retain the full file as received, including its existing name and any accompanying messages or export notes.
2. Identify who supplied it, the device or system it came from, and any earlier version that may still exist.
3. Keep a separate copy for listening, viewing and processing. Save new outputs under distinct names.

If you only have a copy, keep it. It may still contain useful information. Ask the person who supplied it whether an earlier file or native export is available, and tell the reviewer what remains unknown.

When another person controls the recording, identify the system and the relevant date, camera and time interval promptly. CCTV and dashcam systems may overwrite footage. For casework, ask the responsible attorney or collector to arrange preservation and collection before routine deletion; file restoration cannot bring back material that was never supplied.

Save the underlying file or native export when it is available, and retain the context needed to identify and open it. A screen recording or an audio recording of a loudspeaker is a different version from the digital source.

If a voicemail or online video cannot be exported, a reference capture may be the only material available. Keep it and describe how it was made. Do not discard it because it is imperfect, or treat it as equivalent to a native source.

Check that an export covers the intended interval and contains the expected audio or camera channel. Keep the surrounding context. Avoid repeated conversion merely to make a file easier to send; ask which format is needed first.

Record who supplied or handled each version, when it moved, where it was kept and what was done to it. Keep these notes with the file set so another person can follow the sequence.

Useful entries include the original file name, source device or account, person making the export, receipt or transfer date, purpose of the action, output name and relevant timestamps. Separate what you observed from what someone else told you.

For example, a simple handling log for a hypothetical interview recording might read:

A practical file log supports later review; it does not itself certify a formal chain of custody. Follow the evidence-handling procedure for the matter. If the earlier history is unknown, write “unknown.” A note created today should not imply that you witnessed an earlier transfer.

Keep the event time, the time you received the file and the file’s displayed timestamps separate. They describe different things and may not agree.

A camera clock may be wrong. Exporting or copying can produce a new file date. Retain the available metadata and record any known time zone or clock discrepancy alongside the file, including how you learned about it. Do not change the source to make the dates match your account.

Metadata can help explain a recording’s history, but a displayed date is not independent proof of when the recorded event occurred.

A matching cryptographic hash supports that the compared file data are unchanged. It does not establish who made the recording or whether the recorded event happened as claimed.

A hash is a calculated value based on file data. If your organization’s procedure uses hashes, have the responsible person record the algorithm, value, file version and time of comparison. Keep the record available with the handling documentation.

The SWGDE collection guidance, version 1.2 (July 2017), distinguishes file integrity from authentication. It also explains that a file without a collection-time hash may be authenticated through other means. Keep the available recording and disclose the gap.

Keep a backup in a separate location from the files used for daily work, using storage permitted for the matter. A working copy on the same laptop will not help if that laptop is lost or fails.

• Retain the source and its accompanying notes in the agreed storage location.
• Keep another copy on separate storage or in another approved location.
• Check that the saved files can still be accessed and that the accompanying information is present.
• Keep track of who can access the copies and any applicable retention instructions.

The Library of Congress personal-audio guide recommends copies in different locations and periodic checks that files remain readable. For casework, apply your organization’s handling requirements when choosing those locations.

A storage account, removable drive or backup service is useful only if the people responsible know where the files are and can still access them.

Yes. You can prepare a separate working copy for listening, clipping or restoration while keeping the complete source unchanged. Name the result so its relationship to the source is clear.

A short clip can help someone locate an exchange, but retain the full recording and identify the clip’s start and end times. A timestamp list may be enough for an initial request, without creating another file.

Keep three roles distinguishable: the source as received, a working or reference copy, and any processed output. A name such as “interview-cleanup-v1” is more useful than overwriting the source or naming several different files “final.” Keep the original file name in your notes.

If someone has already used editing software or AI cleanup, keep that version too. Record the source used and the processing known to you. Earlier work can be useful context; it should not erase the route back to the recording you started with.

No. A clearer recording does not, by itself, establish authenticity, exact words or a speaker’s identity. Preservation and restoration address different parts of the work.

Media Medic’s main service is restoration. Transcripts and authentication are paid additions, with their scope agreed separately. An enhancement request should not assume a report, testimony or a legal conclusion is included. See our guide to enhancement, transcription and authentication, or discuss a specific authenticity question before further processing.

For a recording that may be used in a matter, agree how the review will stay neutral:

• Describe the passage and the question without asking the reviewer to confirm a preferred account. Keep uncertain words or events marked as uncertain.
• Disclose earlier cleanup, clipping or AI processing. Ask which source and working copy will be used, how changes will be recorded and how the result will be compared with the source.
• Ask who will perform the defined examination, what relevant training and experience they have, and what limitations or further review may be needed.

These questions do not establish a credential or decide court use. Agree any court-use or authentication requirements separately with the responsible legal professional and reviewer.

Confirm the permitted file version, recipient, transfer method and handling requirements before sending sensitive material. Start by describing what you have; arrange file sharing once those questions are clear.

• Which version does the reviewer need for the agreed task?
• Who is permitted to receive or access it?
• What storage, retention or deletion requirements apply?
• Are there restrictions on disclosing names, voices or other identifying information?

If a redacted or shortened version is needed for a particular audience, agree on that purpose and keep it separate from the source. Ask about the actual service arrangements rather than assuming particular controls from an upload option.

If someone may be monitoring the device or account, saving or sharing a recording can expose that activity. Tech Safety Canada’s specialist guidance discusses this situation. Seek appropriate safety support before acting on a general file checklist.

For an organization’s recording, ask its designated contact and counsel, where involved, to confirm who can authorize review and approve onward sharing. Agree which source and working versions, handling logs and identifying details must be retained, who is responsible for them and what must happen before deletion. Check how a confidential source’s identity should be handled before including it in filenames, notes or a request. If authority to obtain or disclose the recording is unclear, resolve that question before sharing it. These questions do not determine legal privilege or replace the organization’s procedure.

Prepare the source or best available copy, the moments that matter, the problem you need assessed and your deadline. You do not need to diagnose the noise or know the technical name for the work.

1. Describe the files. Give the recording type and file count, where they came from, and whether the original or an export is available.
2. Identify the passage. Supply timestamps or explain how to locate the relevant moment. Say if you are not sure.
3. Describe the difficulty. For example, a voice may be too quiet, overlap another speaker or be obscured by traffic. Describe what is hard to follow without supplying words you expect to hear.
4. List earlier processing. Keep those versions separate and explain what was tried.
5. State the deadline and handling needs. Confirm both before arranging file sharing.

Media Medic offers a free file review. An audio engineer listens to every file before an invoice is sent, so you can understand whether restoration may help and agree on the paid work. Normal turnaround is five days or less; a paid 24-hour upgrade is available. Confirm timing for your request.

Continue to audio enhancement or video cleanup, or request a free file review.