Loss of evidence / failure to disclose unused material
1. Where the prosecution fails to take action to obtain relevant evidence or, having done so, the evidence is lost or destroyed, there may be an abuse of process.
2. There may also be an abuse of process if the prosecution fails to comply with disclosure obligations in respect of unused material.
3. The courts will consider the following factors in deciding whether, in the circumstances of the case, there has been an abuse of process 1:
- the extent of the duty, if any, on the investigating authority and/or prosecutor to obtain and/or retain the evidence (having regard to the provisions of Criminal Procedure and Investigations Act (CPIA) 1996 and the Attorney General’s guidelines on disclosure of unused material - see guidance in the Pre-trial section for investigations commenced before 4 April 2005 and those commenced on or after that date);
- if there was no breach of the duty, the trial cannot be unfair on that ground. If there was a breach, proceedings should only be halted if the defence prove on the balance of probabilities that there would be serious prejudice so that no fair trial can be held;
- if the behaviour of the prosecution was so bad that it would not be fair for the defendant to be tried then the case could be halted. The defence would have to show bad faith or serious fault on the part of the investigators and/or the prosecution2.
- R (Ebrahim) v Feltham Magistrates Court: Mouatt v DPP  1 W.L.R. 1293.
- R v Horseferry Road Magistrates’ Court ex p. Bennett  1 AC 42, HL; R v Malcolm John Winter, unreported, 28 November 2007, CA.