OMEGA ยท evidence witness
Can a record's evidence be independently reconstructed?
The evidence witness grades a record by one question: can its evidence be re-derived independently, or must you take the record's word for it. It grades reconstructibility, not truth. It does not decide whether the record is true, the decision was correct, or the control was adequate.
A record cannot witness itself: the highest grade requires an independent external reference, not more of the record.
The grading ladder
A grade is assigned only by running the relevant check, never by trusting a field.
- asserted. A bare claim, nothing to recompute.
- attached. An artifact with an integrity hash, but no way to re-derive it.
- reconstructible / match, re-derived from its inputs, and it agrees.
- diverged, re-derived, and it disagrees. The loudest signal.
- reconstruction-error, the check itself could not run.
An important scoping point the grader's own output carries: re-deriving a value from the producer's own published inputs is self-consistency, not independent corroboration. A "match" at that level detects a transcription error or a producer misapplying its own rule, and nothing more.
Status
The grader is real and runs offline, but its current source is an unpublished working tree with no committed provenance. A public version that reproduces from a clean clone is being prepared as a normal publish-and-verify task, after clearing third-party personal data from a bundled test corpus, checking the redistribution terms of each external data source separately, adding a licence, and reconciling an internal version disagreement. Until that clone is verified, no graded result is published here and the browser grader is not embedded. The reproducibility boundary will be stated on the published page: the grader is deterministic, but its inputs are point-in-time captures of external vulnerability databases, so re-capturing them later changes the graded value. That is a property of the artifact, not a defect.