There were growing calls today for the resignation of Northern Ireland's police ombudsman Al Hutchinson and one of his top investigators.
The watchdog is a key part of the region's new-look policing structures, but it is facing a growing crisis after a leaked report questioned its independence.
The review by the Criminal Justice Inspection (CJI) is the latest in a barrage of criticism that has seen the office accused of failing to properly investigate police wrongdoing in cases linked to the Troubles.
Three human rights groups, which lobby for the victims of violence, have said the leak supports their concerns over the ombudsman, including their fear that reports into historic cases have been altered, removing criticism of the police.
The London-based British-Irish Rights Watch (BIRW) group is the latest to call for the resignation of the organisation's figureheads, former Canadian police commander Al Hutchinson and his former Scotland Yard senior director of investigations Jim Coupland - though their office has previously denied any wrongdoing.
Mr Coupland went on long-term sick leave in June 2010 and in July this year the Ombudsman commissioned an independent investigation linked to the senior director of investigations, but related to issues separate from those raised by the CJI.
BIRW director Jane Winter said: "The findings ascribed to the CJI report closely echo our own concerns about the leadership of PONI (Police Ombudsman of Northern Ireland).
"BIRW has long supported the need for independent scrutiny of alleged police misconduct."
But she added: "We believe that the CJI are correct in coming to the shocking conclusion that PONI reports were re-written or altered to exclude criticism of the police without explanation."
The comments come after the Belfast-based investigative journalism group, The Detail, obtained the leaked CJI report.
The Detail, which published lengthy extracts of the leak on its website, said the draft report made a series of damaging findings, including a "lowering of independence" in the ombudsman's office, which should see its role in investigating historic murders suspended.
The CJI said it was not its policy to comment on draft reports.
The police ombudsman's office said it will not be commenting ahead of the publication of a final report.
But the CJI review has now been passed to Stormont Justice Minister David Ford, who has said he will publish it in early September.
Political pressure is growing, however, for an earlier publication of the findings.
The Ombudsman's office was established around the time of sweeping changes in policing that saw the RUC replaced by the reformed Police Service of Northern Ireland (PSNI).
The new ombudsman's office has its own team of investigators and it was intended that it would end the process of the police investigating themselves.
But with the CJI leak fuelling fears that there is too close a relationship between the ombudsman's office, the PSNI and the Northern Ireland Office (NIO), critics have said the credibility of the key building block in the new era of policing is at risk.
Sinn Fein's Gerry Kelly said: "We have already called for Al Hutchinson to resign. If the leaks in the CJI report are true then it seems what has been going on within the Police Ombudsman's Office is actually even worse than people had feared."
SDLP justice spokesman Alban Maginness also said: "If this leaked report is correct then the Ombudsman's position is untenable and, without doubt, he must go."