Disclosure
In criminal proceedings, the prosecution's duty to give the defence any retained material that might reasonably be considered capable of undermining the prosecution case or assisting the defence case. Governed by the Criminal Procedure and Investigations Act 1996 and the Attorney General's Guidelines. (In civil proceedings the equivalent process is usually called 'Disclosure (Civil)'.)
Independent editorial summary — not the official statute text. Read the official version on legislation.gov.uk.
CPS guidance defines the duty precisely: 'Disclosure refers to providing the defence with copies of, or access to, any material which might reasonably be considered capable of undermining the case for the prosecution against the accused, or of assisting the case for the accused, and which has not previously been disclosed.' Applying that definition to a given piece of material is described as 'the Disclosure Test', and the guidance is explicit that the test 'does not include an assessment as to whether the material is or could be admissible in a trial, or the merits of a defence' — the question is only whether the material could help the defence or hurt the prosecution, not whether it would actually be used at trial.
Disclosure is preceded by a separate step, 'revelation': the police alerting the prosecutor to material that exists, which 'does not mean automatic disclosure to the defence' — the prosecutor still has to apply the test. The duty is also continuing rather than one-off: 'The duty on a prosecutor to review material is an ongoing one and the disclosure should be kept under continuous review throughout proceedings.' Getting it wrong has real consequences: guidance warns that 'A failure by the prosecutor or the police to comply with their respective obligations under the CPIA or Code of Practice may result in a defence application to stay proceedings as an abuse of process, the exclusion of material evidence or a successful appeal', although case law shows courts will not necessarily stay a case for disclosure failures if 'the trial process could correct the prejudice caused.'
Related terms
Official sources
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