"To help guarantee a fair trial a defendant has the right to be provided with any material which could assist them in defending themselves. They have a right to an open and honest prosecution which reveals any weakness in the case against them. Investigators must pursue all
reasonable lines of enquiry and this includes investigating matters which could point towards innocence as well as guilt.
When a defendant is charged with an offence, prosecutors are required to provide the defence with any material that undermines the case for the prosecution or assists the case for the defendant. This could be, for example, CCTV footage, statements from witnesses, mobile phone messages, social media conversations or photographs.
The CPS and the police have a duty to keep disclosure under review throughout the life of a case. If new material comes to light in the lead up to a trial, or during a trial, then that material will be reviewed by prosecutors who will determine if it has any impact on the proceedings.
Etc."
www.cps.gov.uk
maximus otter