All rape and serious sexual assault cases in England and Wales are being reviewed by the Crown Prosecution Service to ensure evidence has been disclosed.
Director of Public Prosecutions Alison Saunders said the steps were being taken to identify any individual cases of concern “as a matter of urgency”.
It comes after a series of rape and sexual assault cases have collapsed.
Ms Saunders admitted that some cases would be halted because of disclosure issues.
“Inevitably, bringing forward these case reviews means it is likely that there may be a number of cases which we will be stopping at around the same time,” she said.
In the lead-up to trials, police and prosecutors are required to hand over relevant material that either undermines the prosecution case or assists the defence case.
But the regime came under sharp focus after defendants facing rape allegations had the charges against them dropped when critical evidence emerged at the 11th hour.
The Crown Prosecution Service, National Police Chiefs’ Council (NPCC) and College of Policing have published a disclosure “improvement plan”.
It set out plans to review training on disclosure, develop a cadre of specialist and experienced disclosure experts in every force and provide all multimedia evidence from the CPS to the defence via direct electronic link by July.
The document also commits to reviewing whether there “should be a requirement for officers to hold a Licence to Practise in respect of disclosure” by January 2019.
Chief Constable Nick Ephgrave, the NPCC lead for criminal justice, said: “Disclosure is an essential element of the criminal justice process, but has too often been seen as an administrative task completed at the end of an investigation, exacerbated by the rapid expansion of digital material involved in almost every case.
“We now need to firmly embed disclosure in the investigative mindset from the outset of any investigation.
“Reviews of recent cases have shown a range of issues leading to failures but there has been no intention by officers to conceal information.”
He expressed confidence the plan will lead to “real improvements in quick time”.
A flurry of cases have raised serious concerns over arrangements surrounding the disclosure to defence teams of evidence.
Last week, a rape case against Oxford University student Oliver Mears was dropped after fresh evidence – including a diary that supported his case – was passed to the Crown Prosecution Service.
Surrey Police admitted “there were flaws in the investigation” after the force failed to examine the accuser’s “digital media” or follow “a reasonable line of enquiry”.