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Qstamp / Evidential integrity
Evidential integrity

Legal tamper proofing for records that must stand up in court.

Courts, tribunals and regulators ask the same questions of every electronic record. Is it authentic, is it complete and unaltered, who made it, and when. The Qstamp family answers each question with evidence that any party can verify independently, for as long as the record must be kept, including after quantum computers are able to forge classical signatures.

Definition

What legal tamper proofing means here.

On this website, legal tamper proofing means that a sealed record cannot be altered, replaced, backdated or removed without the change being detected by any independent verifier. Qstamp does not physically prevent a custodian from editing its own copy of a record. It makes every such edit provable, which is what a court or regulator needs in order to rely on the record.

The questions courts ask

Each evidential question, and the evidence the family supplies.

QuestionWhat must be shownEvidence supplied
AuthenticityThe record is what it is claimed to beAn ML DSA signature by the key of the producing person or system, and a published key description
IntegrityThe record has not been altered since it was madeA SHA3 fingerprint fixed in a signed and anchored commitment
TimeThe record existed no later than a stated timeThe time of a block finalised by a post quantum validator committee
AttributionThe record was made by the party said to have made itThe signer key bound into the statement and into the anchoring transaction
CompletenessNo record in a series has been removed or insertedHash chained logs and sequenced records with running totals
ContinuityThe chain of custody is unbrokenEach handover sealed as its own record, linked to the record before it
DurabilityThe evidence remains reliable for the retention periodPost quantum signatures across the full history of the network
By jurisdiction

Rules on electronic evidence the family is designed to support.

The instruments below govern the admissibility or the weight of electronic records and time stamps. Whether a record is admitted, and what weight it carries, is always a matter for the court.

JurisdictionInstrumentRelevance
United StatesFederal Rules of Evidence, Rule 902(13) and 902(14)Self authentication of records generated by an electronic process and of data identified by a process of digital identification, such as a hash
United StatesFederal Rules of Evidence, Rule 901(b)(9)Authentication by evidence describing a process or system and showing that it produces an accurate result
European UnioneIDAS, Articles 41 and 42Legal effect of electronic time stamps and the presumption attaching to qualified time stamps issued by qualified trust service providers
European UnioneIDAS 2, Articles 45h and 45iLegal effect of electronic ledgers and requirements for qualified electronic ledgers
United KingdomElectronic Communications Act 2000, section 7Admissibility of electronic signatures and related certificates
SingaporeEvidence Act 1893, section 116APresumptions relating to electronic records and the systems that produce them
IndiaBharatiya Sakshya Adhiniyam 2023, section 63Admissibility of electronic records supported by a certificate that includes the hash value of the record
PhilippinesRules on Electronic EvidenceAuthentication and integrity of electronic documents and electronic signatures
InternationalUNCITRAL Model Law on Electronic Commerce, Article 9Admissibility and evidential weight of data messages, with regard to the reliability of the manner in which integrity was maintained
Standards

Technical standards for digital evidence.

StandardSubjectRelationship to Qstamp
ISO/IEC 27037Identification, collection, acquisition and preservation of digital evidenceFingerprints and receipts support preservation and later demonstration of integrity
ISO 14641Information systems for the preservation of electronic documentsAnchored commitments supply independent evidence that preserved documents are unchanged
RFC 3161Time stamp protocol using a trusted time stamping authorityQstamp provides time evidence without reliance on a single authority, using post quantum signatures
RFC 9162Certificate Transparency version 2.0Qstamp uses its Merkle tree construction for inclusion proofs
Producing evidence

How a sealed record is put before a court.

  1. 01Preserve

    The record, its envelope and its receipt are preserved together under the retention policy of the producer.

  2. 02Disclose

    The producer discloses the record, the envelope, the receipt and the published key description of the signer.

  3. 03Verify

    Any party verifies the record with the open source verifier or the published procedure, without the producer's systems.

  4. 04Explain

    An expert describes the process and its result, using the published construction and the verification output.

  5. 05Weigh

    The court decides admissibility and weight under its own rules of evidence.

Limits

What the evidence does not show.

A sealed record shows that its content is unchanged since sealing, who sealed it and when. It does not show that the content is true, that the signer was entitled to sign, or that an event outside the record took place. Qstamp is not a qualified trust service under eIDAS, and Quantova Inc does not give legal advice on admissibility in any jurisdiction.