Legal evidence
Records for a chain of custody in evidence photography, from card to exhibit
A photograph is carried into a case by the person who vouches for it. For most working photographers, that is you. Lumethic gives every frame on a card an independent date at the first backup and gives the delivered images a verified link to the camera original, so that account has records behind it if it is ever questioned.
The problem
"How do we know this file hasn't been changed?"
Between the shoot and the hearing, a photograph passes through cards, laptops, editing software, and email. Without records, the honest answer to when a file could last have been altered is "any time before today". Challenges are uncommon, and photographs come into a case through the person who vouches for them. But that question cannot be answered after the fact, and AI tools have made it easier to ask.
One thing first: we build software and do not give legal advice. The people running the case should define what they need from the photography, ideally in writing before the first shoot. What we provide is the technical record that supports the account of whoever vouches for the photograph.
What you get
Records for every stage of the work
Every frame, dated at the first backup
When you back up a card with OffShoot, Silverstack or ShotPut Pro, or hash the ingested folder with hashdeep, Lumethic anchors the hash list with an independent timestamp authority. With a content-binding checksum (C4 in ASC MHL, or SHA-256) the receipt proves every file existed byte for byte no later than that time. With xxHash it proves only that the offload took place. One receipt covers the whole card, and the grade is printed on it.
Verification of the exhibits
The frames that go to the attorneys or become exhibits get a RAW and JPEG comparison: sensor checks, structural similarity, recapture detection, metadata consistency, with the methodology version and scores stated. Because the files match the anchored list, the report shows the chain from first backup to verification. Exhibits edited in Photoshop verify the same way.
Records the legal team can open
Reports and receipts are shared with the legal team via link; nobody needs an account. A one-page requirements sheet tells a firm or consultancy what to ask of the next photographer. The Lightroom plugin, on paid plans, checks on export that a JPEG derives from its verified RAW and embeds Content Credentials; it is optional.
How it works
From the memory card to the exhibit
The record starts at the first backup and follows the images through selection, processing, and handover. Each stage produces something the legal team, and the other side, can check.
Anchor the card at the first backup
Back up the card with your offload tool, or hash the ingested folder with hashdeep. Upload the hash list and Lumethic has it timestamped by an independent authority. The receipt covers the whole card and proves every frame existed no later than that time, byte for byte when the list uses a content-binding checksum. Nothing covers the card before the backup, so back up on the day you shoot.
Verify the selects
When the relevant frames are chosen, submit each one as a RAW and JPEG pair. The comparison covers sensor characteristics, structural similarity, recapture detection, and metadata consistency, states its methodology version and scores, and the files match the anchored list.
Export and verify the exhibits
Export exhibits from Photoshop or Lightroom as usual and verify them as RAW and JPEG pairs. Cropping, exposure, white balance, lens and perspective correction, dust removal and annotation are expected to pass; compositing, object removal and generative fill are expected to fail. The Lightroom plugin can run that check on export and embed Content Credentials; it needs a paid plan and is optional.
Hand over via link
Reports and receipts are shared with attorneys and experts through private links. Nobody needs an account, and each record contains what is needed to check it with standard cryptographic tools.
A worked example
Ten days of field documentation, end to end
Here is how the pieces fit together on a typical engagement: a commercial photographer hired to document a scientific sampling study whose results are headed for litigation.
Before day one
The attorneys put in writing what they need from the photography. The photographer sets the camera's date, time, and time zone, configures it to write RAW and JPEG, and runs a test offload to confirm that the hashes of the card copies match the tethered copies. The offload tool is set to C4 checksums. A Basic plan is enough to start.
Each shoot day
After shooting, the card's write-protect switch goes on and the card is backed up in the field. The offload tool writes its hash list and uploads it automatically, so every card is anchored with an independent timestamp on the day it is backed up, which on this job is the shoot day. Field notes reference the card labels. Ten days of shooting produce a stack of receipts that together cover every frame taken, well inside the monthly allowance.
Selection, weeks later
The legal team picks roughly a hundred frames for the expert report. The photographer verifies each one as a RAW and JPEG pair. Because the files match the anchored lists, every report shows the chain: backed up and anchored on the shoot day, verified. Nothing else from the shoot needs verifying.
Exhibits and handover
Exhibit files are exported from Photoshop and verified as RAW and JPEG pairs. Reports and receipts go to the attorneys as links, together with the one-page requirements sheet for the next engagement. When the opposing expert wants to check the record, the receipt verifies with standard tools, without trusting anyone's word for it.
The result: when the after-the-fact objection comes, the answer is not an argument but a stack of records, each one independently checkable, reaching back to the day each card was first backed up.
The records
Open the records the way an opposing expert would
A record only helps if the other side can open and check it. Both of the pages below are public. Before you decide anything, look at what the legal team would actually receive.
A shared verification report
The report states what was checked, the scores, and the methodology version. This is what attorneys see when you share a verified exhibit with them via link.
View the sample reportThe public receipt check
Any offload receipt can be verified on a public page, without an account and without trusting Lumethic. Opposing experts use the same page.
Check a receiptIn the courtroom
Built to back up testimony, not replace it
Hashing and verification do not make a photograph admissible by themselves. They protect the testimony that does, and every part of the record can be examined by the other side.
- Offload receipts contain everything needed to check them with standard cryptographic tools, independent of Lumethic, and there is a public page where anyone, including opposing experts, can verify a receipt directly.
- Verification reports state their methodology version, scores, and thresholds, so the analysis can be explained and examined rather than presented as a black box. Validation so far covers calibration on 397 genuine images of one class and a recapture evaluation on twelve files. Error rates for manipulated pairs are not yet published, and contested authenticity opinions belong to a qualified examiner.
- The record answers the after-the-fact objection: it shows the files have not changed since they were first anchored, and that the exhibit is consistent with the verified camera original. If a challenge is raised and taken seriously, the side offering the photograph needs the originals, metadata that agrees with the account, and a date that no party controlled. None of that can be created afterwards.
Questions from evidence work
Planned
A Legal package, if the demand is there
Anchoring and verification already work on both paid plans. If you handle cases regularly, tell us what would earn a separate package: evidence-report wording, a matter archive, annual billing, or something we have not thought of.
Whether it gets built depends on whether it is wanted. If it fits your work, a short mail is enough; we reply with the current prices and count every reply.
I want thisSet up the record before the first shoot
Both paid plans include card offloads. Card receipts cover every frame; verification is only needed for the exhibits. Annual billing is available, and receipts and reports are yours to download and keep.