A subject access request can land on a desk in the middle of an active investigation. The Data Protection Act 2018 lets you withhold data where disclosure would prejudice a crime, tax or immigration matter, but the exemption is deliberately narrow. It applies only to the extent prejudice would actually occur, not as a blanket withhold across an entire file.

This guide covers the five bases in Schedule 2 that let you restrict access to protect crime, tax, immigration and public protection functions, and explains why partial disclosure, not outright refusal, is usually the correct outcome. Download it to see how the prejudice test should be applied document by document, not case by case.