Supervision (Communications Surveillance)

A legal hold (or litigation hold) is a directive that suspends the normal deletion or modification of records relevant to anticipated or pending litigation, investigation, or audit. Data under hold is preserved unaltered — overriding retention schedules — until the hold is released.

Chain of custody is the documented, unbroken record of how electronic evidence was captured, stored, accessed, and produced — who handled it, when, and what was done. A defensible chain of custody establishes that archived data is authentic and has not been tampered with.

An audit trail is a chronological, tamper-evident log of actions taken within a system — searches, exports, policy changes, and access. Audit trails demonstrate accountability and are required by many compliance regimes to prove how records and the archive itself were handled.

Personally Identifiable Information (PII) is data that can identify an individual; Protected Health Information (PHI) is health data tied to an individual under HIPAA. Archives detect and govern PII/PHI to apply the right security, retention, and privacy controls.