Unbreakable, cryptographic evidence trail
Digital evidence is only as strong as its chain of custody. FrameCounsel creates a cryptographic, immutable audit trail for every piece of evidence from the moment it is imported. SHA-256 hashing at ingestion, append-only event logging for every access and modification, and automated integrity verification at each step ensure that defense attorneys can prove evidence has not been tampered with — or demonstrate when the prosecution cannot prove the same.
A streamlined workflow designed for defense attorneys, not forensic engineers.
When evidence is imported, FrameCounsel immediately computes a SHA-256 hash of the original file. This cryptographic fingerprint is stored in the append-only audit log with a timestamp.
Every time an evidence file is accessed, analyzed, or referenced, FrameCounsel re-verifies its hash against the original. Any discrepancy triggers an immediate integrity alert.
Every action taken on evidence is logged immutably: who accessed it, when, what analysis was performed, and what results were generated. The log cannot be edited or deleted.
Generate a chain of custody report documenting the complete history of each evidence file — from original hash at import through every access and analysis — formatted for court filing.
Purpose-built capabilities for criminal defense evidence analysis.
Industry-standard cryptographic hashing verifies file integrity. Any modification — even a single bit — changes the hash, making tampering immediately detectable.
An immutable, append-only log records every action taken on every evidence file. The log cannot be edited, backdated, or deleted, ensuring a tamper-proof record.
FrameCounsel automatically re-verifies evidence hashes before any analysis operation. If a file has been modified outside the system, you will know immediately.
Designate an external SSD (like the SanDisk PRO-G40) as a dedicated evidence vault. When disconnected, your evidence is physically secured in your control.
Generate chain of custody documentation formatted for court filing, including hash values, timestamps, access logs, and integrity verification status.
Use FrameCounsel's chain of custody tools to audit prosecution evidence. Request hash values and access logs — if they cannot provide them, challenge the evidence's integrity.
How defense teams use this capability to protect their clients' rights.
Scenario
The prosecution presents dashcam footage as evidence. The defense suspects the footage may have been edited — the video appears to have a suspicious jump cut at a critical moment.
Outcome
Defense requests the original file's hash from the prosecution. FrameCounsel computes the hash of the provided file and compares it against standard video format structures, identifying that the file's container metadata indicates post-capture modification. The chain of custody challenge leads to a Daubert hearing on the evidence's reliability.
Scenario
A defense investigator collects witness interview recordings and surveillance footage. The case goes to trial 18 months later, and the prosecution challenges whether the defense's evidence has been preserved properly.
Outcome
FrameCounsel's chain of custody report shows the SHA-256 hash computed at import, every access event over 18 months, and verification that the current file matches the original hash exactly. The documentation defeats the prosecution's challenge to the evidence's integrity.
Scenario
A complex case involves body camera footage from police, surveillance from three businesses, and two bystander cell phone videos. The defense needs to document the provenance of each piece.
Outcome
FrameCounsel's audit trail documents when each file was received, from whom, its original hash, and the complete analysis history. The chain of custody report covers all 7 evidence sources in a single court-ready document.
Cryptographic Evidence Management
SHA-256 hashing computed at import with HMAC verification for hash integrity
Append-only SQLite audit log with write-ahead logging for crash resistance
Every log entry includes timestamp, action type, user identity, and evidence file reference
Automatic hash re-verification before any analysis operation
External evidence vault support with FileVault encryption on macOS
Chain of custody reports generated as PDF with embedded hash values and digital signatures
All custody data stored locally — no cloud synchronization or external logging
Compliant with NIST SP 800-86 guidelines for digital evidence handling
Common questions about chain of custody & evidence integrity.
SHA-256 is a cryptographic hash function that generates a unique 256-bit fingerprint for any file. Even changing a single bit in a file completely changes its hash. This means if you compute the hash at import and the hash matches later, you can mathematically prove the file has not been modified. It is the standard used by federal agencies, NIST, and forensic laboratories for digital evidence integrity.
The audit log uses an append-only architecture — new entries are added sequentially and previous entries cannot be modified or deleted through the application. The log file itself is stored in a protected location on your Mac. For maximum security, you can store your evidence project on an encrypted external SSD that you physically control.
Yes. When you move a FrameCounsel project to a new machine, the complete audit trail and all hash records move with it. FrameCounsel will verify evidence integrity on the new machine and add a "project migration" entry to the audit log documenting the transfer.
The chain of custody report is designed to meet the evidentiary standards for digital evidence documentation. It includes all information typically required: original hash values, timestamps, access logs, and integrity verification. The report's admissibility depends on your jurisdiction's specific rules, but it provides the technical foundation needed to authenticate digital evidence.
Blog posts, case studies, and documentation related to this feature.
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