1. Meaning in Swiss Legal Context

(A) Electronic Trust Archive

In probate practice, this refers to:

• digital wills,
• encrypted estate records,
• blockchain or notarized digital storage,
• cloud-based succession files,
• executor-managed electronic estate registers.

Swiss law treats these as part of the digital estate, which generally passes to heirs under universal succession principles.

(B) Checksum / Hash Integrity

A checksum (or cryptographic hash) is used to prove:

• the file has not been altered,
• the document is authentic,
• the digital record remains intact.

Under Swiss evidentiary principles, this falls under:

• integrity of digital records
• authenticity of documents
• free judicial evaluation of evidence

Swiss courts do not automatically accept electronic integrity proofs; they assess credibility case-by-case.

(C) “Checksum Drift”

This is not a legal term but would be interpreted as:

• mismatch between stored hash values over time,
• alteration of digital probate files,
• corruption or manipulation of estate records,
• or forensic inconsistency in electronic archives.

Legally, it triggers:

• suspicion of document tampering
• burden shift in proof disputes
• forensic authentication requirements

2. Legal Framework in Switzerland

Key principles applied in probate disputes:

• Universal succession (Art. 560 ZGB) → heirs inherit all assets including digital data 
• Free evaluation of evidence by judges
• Digital documents are admissible as evidence if relevant and authentic 
• Authenticity and integrity are decisive factors for digital records 

3. How Courts Treat “Checksum Drift” Situations

In Swiss probate litigation, if digital estate records show mismatch (drift):

Courts generally apply:

1. Presumption of integrity if system is reliable
2. Reversal of burden if tampering is plausible
3. Expert forensic evaluation (IT + crypto audit)
4. Free judicial discretion in credibility assessment

4. Relevant Swiss Case Law (Analogous Principles)

Below are 6 key Swiss legal precedents / Federal Supreme Court principles relevant to digital integrity, electronic evidence, and probate disputes:

1. BGE 111 IV 119 (Computer Data as Documentary Evidence)

• Computer-stored data qualifies as “documentary evidence”
• Even if not directly readable, it is legally relevant evidence
• Alteration of such data can constitute falsification

➡ Principle: Digital records have full evidentiary status if intended to prove legal facts

2. Federal Supreme Court – Free Evaluation of Evidence Principle (General Civil Procedure Doctrine)

• Judges are free to decide reliability of electronic signatures and documents
• No automatic presumption of validity for digital records

➡ Applied in probate: checksum drift only matters if court doubts authenticity

3. BGE 130 III 321 (Burden of Proof in Document Authenticity)

• Party challenging authenticity must show probability of defect
• Once credibility is challenged, opposing party must prove validity

➡ Direct relevance: checksum drift shifts burden to estate executor or custodian

4. BGE 5A_666/2012 (Will Authenticity & Date Integrity)

• Court emphasized importance of authenticity and consistency of testamentary documents
• Inconsistencies trigger evidentiary scrutiny

➡ Analogous to digital probate file integrity issues

5. Federal Supreme Court Decision 4A_522/2018 (Probate & Information Rights)

• Heirs have limited but enforceable rights to estate information
• Banks or custodians may resist disclosure under privacy, but courts balance access rights

➡ Relevant to digital archives held by trustees or platforms

6. Swiss Federal Supreme Court Doctrine on Digital Evidence (CCP Art. 177 Interpretation)

• Electronic records are admissible like traditional documents
• Integrity is key factor in probative value
• Courts focus on whether data was altered or reliably stored

➡ Core principle for checksum-based verification disputes

7. (Supplementary Principle) Digital Chain of Custody Doctrine (Swiss Forensic Practice)

• Evidence must maintain traceability from creation to court
• Any break in integrity chain reduces evidentiary weight

➡ Direct analogy to “checksum drift” in probate archives

5. Practical Legal Interpretation of “Checksum Drift in Probate Review”

In Swiss probate disputes, checksum drift would typically be argued as:

A. Allegation of tampering

• digital will or estate file modified after death

B. Technical integrity failure

• system migration errors, cloud corruption, encryption mismatch

C. Evidentiary weakening

• reduces trust in digital archive authenticity

D. Court response

• forensic IT expert appointment
• comparison with backup hashes
• evaluation of system reliability

6. Conclusion

In Switzerland, “Electronic Trust Archive Checksum Drift in Probate Review” is legally treated under:

• digital evidence integrity rules
• inheritance law (ZGB succession rules)
• civil procedure evidentiary evaluation
• forensic authentication standards

Swiss courts do not recognize checksum drift as a legal doctrine, but they treat it as a serious evidentiary integrity issue that can influence probate outcomes, especially where digital wills or electronic estate archives are contested.