Question to the Attorney General:

To ask Her Majesty's Government how many prosecution cases have collapsed because of a failure to disclose evidence in the last two years.

Prosecutors should identify and, where appropriate, seek to rectify evidential weaknesses in a case. However, they should stop cases which do not meet the evidential stage of the Full Code Test in the Code for Crown Prosecutors and which cannot be strengthened by further investigation, or where the public interest clearly does not require a prosecution. There is a continuing duty of review throughout the case.

Internal CPS case outcome recording data for 2015-17 shows that issues connected to the disclosure of unused material were recorded as the primary reason in 0.81% of all prosecutions that did not result in a conviction.

Other reasons prosecutions may be stopped include that new material reviewed during the case reveals evidence which undermines the prosecution case, key witnesses do not attend, key evidence is ruled inadmissible, or other circumstances change to the extent that a charge no longer meets the evidential stage of the Full Code Test.

The most frequent reason that a prosecution did not result in a conviction was that the defendant was acquitted after trial. This was the reason in 25% of such cases.