A former top loyalist turned supergrass won High Court permission to challenge the police refusal to provide him with his interview tapes.
Gary Haggarty, who is currently on remand charged with the murder of a taxi driver in Belfast 14 years ago, was granted leave to seek a judicial review of the non-disclosure.
His lawyers claim delay in handing over the material could interrupt both his trial and any proceedings at which he appears as a prosecution witness.
Haggarty (39), from north Belfast, is being held over the murder of William Harbinson in May 1997. Charges were brought against him and another one-time senior loyalist following a new investigation by detectives from the Historical Enquiries Team.
But in January 2010 Haggarty signed an agreement to become an “assisting offender” under the terms of the Serious Organised Crime and Police Act.
As part of that pact he underwent a debriefing process which involved phases of two-week interviews at an unknown location in Britain.
Haggarty brought judicial review proceedings to gain access to the tape recordings so that his solicitor can prepare the defence case and advise him.