The Investigation Standard — What “Reasonable” Actually Looks Like

Investigations fail when they drift: vague scope, unclear roles, and “quiet fixes” running alongside the process. ACAS guidance is clear that a reasonable investigation is central to fairness.

Key takeaways

Start with tight Terms of Reference (scope and questions)

Keep independence: investigator gathers facts; decision-maker decides

Use a proportionate evidence plan and document rationale

The 5 essentials (non-negotiables)

Terms of Reference: what’s in scope, out of scope, and what questions must be answered.

Independence: avoid conflicts; where trustees/execs are already involved, consider external support.

Evidence plan: documents, witnesses, and timeline—defined before interviews start.

Structured interviews: context → specifics → impact → corroboration → close.

Evidence-based findings: show what you relied on, what you rejected, and why.

Need this done properly without over-engineering? LSK Evolv provides a ToR template, interview scripts, and independent investigations designed to withstand scrutiny and protect organizational trust.