Chain of Custody for Digital Evidence Is Getting International Attention. Insurance Claims Are Behind.
A claims file gets flagged for discovery. Opposing counsel wants to know who had access to the photos, when they were uploaded, and whether anything changed between the loss date and the day the claim was filed. The adjuster can produce the photos. Proving the custody chain around them is a different exercise entirely, and most claims systems weren't built to answer it.
A recent article in Frontiers examines how blockchain-based chain-of-custody systems are being proposed for digital evidence in post-conflict prosecutions, where investigators across multiple countries and agencies need to prove an unbroken record of who handled evidence and when. The stakes are different from a property claim. The underlying problem isn't. Digital evidence passes through hands. Every handoff is a place where a defense attorney, or opposing counsel in a coverage dispute, can ask: how do we know this wasn't altered?
What Blockchain Timestamps Actually Prove
A blockchain anchor establishes two things well: that a specific file existed in a specific state at a specific time, and that the file hasn't changed since. It does this by hashing the file (SHA-256, a one-way fingerprint) and recording that hash on a public ledger. Change one pixel of the photo, the hash changes completely, and the anchored record no longer matches.
What it doesn't do on its own is document every hand the file passed through afterward. An anchor proves the file existed unaltered at time X. It doesn't log who opened it, forwarded it, or downloaded a copy on day 47 of the claim. That's a custody log's job, not a timestamp's job. Vendors who blur that line set clients up to overstate what a court will accept.
The two capabilities work together. A timestamp anchors the starting point. A custody log tracks everything after. Claims teams that only have one are missing half the record.
Where the Legal Standards Actually Apply
FRE 901(b)(9) authenticates evidence produced by "a process or system that produces an accurate result." It's the standard most commonly cited for blockchain evidence, and it requires laying a foundation, typically expert testimony explaining how the hashing and anchoring process works and why it's reliable. It's a real path. It's not a shortcut.
FRE 902(13) and 902(14), added in 2017, are different. They allow self-authentication of machine-generated records through written certification, no live witness required. A certified record showing a file's SHA-256 hash matches what's recorded on a public blockchain fits squarely inside what these rules were written for. They're underused relative to how well they map onto this exact evidence type, and litigation teams that only reach for 901(b)(9) are doing more work than the rules require.
These aren't interchangeable, and treating them as the same authentication path is a mistake worth avoiding. 901(b)(9) gets you in the door through testimony about the process. 902(13) and 902(14) get you in the door through certification, without the witness. Which one applies depends on how the evidence is being offered, not on which sounds more impressive in a brief.
Why the Anchor Needs to Be Independent of the File
The Frontiers piece on post-conflict evidence and a related article on how blockchain can improve digital evidence collection both point at the same structural requirement: the record of custody has to survive independently of the file itself. If the proof lives only inside the file's metadata, it's gone the moment the file gets re-saved, converted, or stripped during transfer. That's exactly what happens to a lot of claims evidence. Photos get pulled off a phone, uploaded to a claims portal, exported to a PDF for the file. Metadata doesn't usually survive that trip intact.
An anchor recorded on a public ledger doesn't depend on the file surviving in its original form. The hash is fixed at the moment of anchoring. Verification later just means re-hashing the current file and checking it against the anchored record. If they match, nothing changed. If they don't, something did, and now you know exactly where in the chain to look.
I designed ProofLedger around anchoring to both Polygon and Bitcoin for this reason. Polygon gives a fast, low-cost anchor. Bitcoin adds a second, independently operated ledger with a much longer track record of being treated as reliable in legal and financial contexts. Two chains means two independent parties would have to be compromised to fake the record, not one. For evidence that might end up in front of a judge, that redundancy is the difference between a timestamp and a defensible timestamp.
What Changes Monday Morning
Most claims workflows treat evidence capture and evidence storage as the same step. They aren't. Capture is the moment a photo, video, or document is created. Storage is everything that happens to it after. A timing challenge in discovery targets the gap between those two moments, and if nothing anchored the file at capture, that gap is undocumented by default.
The fix isn't complicated. Anchor the hash at or near the point of capture, before the file enters a claims system where it can be copied, converted, or re-uploaded. Keep a separate custody log for everything that happens afterward. Cite the right rule for the right situation, 901(b)(9) when you're laying a foundation through testimony, 902(13) or 902(14) when you're offering a certified record instead.
Has your team's evidence workflow ever been challenged specifically on when a file was captured, separate from whether it was authentic? That's a narrower question than most authentication challenges, and it's becoming a more common one.