Admissibility: The Three Gates

Core idea

Whether evidence is admissible generally depends on three questions. Chain-of-custody failures most commonly defeat the authenticity and reliability gates, and hashing plus timestamping plus a contemporaneous log plus minimum handlers defends all three.

Components

• Relevance: does it help establish a fact in issue?
• Authenticity: can you prove it is what you say it is?
• Reliability: is the method of collection trustworthy?

When to use

When preparing an evidence pack or assessing whether a preserved artefact will survive challenge in a legal or regulatory setting.

Example

A screenshot with a SHA-256 hash logged at capture, an OpenTimestamps commitment, and a contemporaneous custody log passes authenticity and reliability; its relevance is established by tying it to a fact in issue (e.g. the exact deposit address that received stolen funds).

Related

Five Evidence Preservation Principles, Custody Log: The Six Questions, Chain of Custody by Evidence Type