Police failing to disclose evidence which could be crucial to defendants is causing a "steady stream of miscarriages of justice", the Crown Prosecution Service Inspectorate said.

The problem is so widespread that addressing each failure could bring courts " to a halt."

A number of recent cases have fallen through after evidence which should have been disclosed earlier was revealed at the eleventh hour. Defendants accused of crimes such as rape, sexual assault or people trafficking, have spent months on remand with charges hanging over them.

Police are meant to disclose unused evidence from their investigations, if it can assist the defendant. However, in many cases this is either being done too late or not being done properly, the all-party Commons Justice Committee was told.

Kevin McGinty, Chief Inspector of the Crown Prosecution Inspectorate, which oversees the work of the Crown Prosecution Service, said the “single most frequent cause” of miscarriages of justice involves police officers' “failure to disclose information which could have assisted the accused”.