Fingerprint the final review bundle
A cryptographic hash converts a file into a fixed-length fingerprint. Changing even a small part of the file produces a different result. A completed review can be hashed and the fingerprint recorded with a timestamp and case reference.
Later, a reviewer can hash the file again. A match supports that the reviewed file is unchanged from the recorded version. The underlying private document does not need to be made public to perform that comparison.
Keep integrity separate from truth
A perfectly preserved fake remains fake. The integrity layer should therefore sit after source verification and human decisions, not replace them. Reports should name the verification sources and unresolved limitations alongside the fingerprint.
- Use a stable final file format and version
- Record the hash algorithm and exact fingerprint
- Timestamp the receipt through a dependable process
- Avoid publishing personal documents or unnecessary metadata
- Explain that matching proves integrity, not authenticity
Blockchain is optional
A blockchain can provide one form of public timestamping, but a conventional signed audit log or trusted timestamp may also meet the product need. Choose the mechanism based on privacy, cost, governance and who must verify the receipt—not because the transaction involves an expensive car.