The RUC Chief Constable Sir Ronnie Flanagan and the North's Police Ombudsman are at odds over who ordered recent arrests in the Robert Hamill murder case.
Sir Ronnie has claimed the arrests last month of seven people, including a reserve constable, were carried out on the direction of the RUC.
However, a spokesman for Ombudsman Nuala O'Loan said they were carried out under her direction.
No-one was charged following the interrogations about the killing of Mr Hamill, a Catholic man who was kicked to death by loyalists in Portadown in April 1997, just yards from an RUC Landrover with officers inside.