A massive row between the Police Ombudsman's chief executive and the head of investigations left staff demoralised, a new report said.
The report was commissioned following a dispute over a pay review that led to chief executive Sam Pollock resigning and senior director of investigations Jim Copeland taking long-term sick leave.
An independent reviewer was called in to probe Mr Pollock's departing claims that the office's independence had been undermined by meddling from senior civil servants in the Department of Justice.
The chair of the Community Relations Council, Tony McCusker, concluded that there had been non-systemic but clear interference. His report said: "The issues triggered by the outcome of the regrading review have, in my view, been highly damaging.
The impact goes beyond those most involved and has had a demoralising impact on the whole office."
Mr Pollock alleged the office's independence had been undermined by meddling from senior civil servants. He resigned in April after making the claims.
One of the allegations involved a job evaluation carried out last year by the Department of Finance and Personnel into the pay grades of senior staff at the Ombudsman's office. The DFP presented its findings to Mr Pollock and confirmed his pay grade, but said that of his senior director of investigations should be higher.
The findings were not well-received and the DFP consultants complained that they were treated in a "wholly inappropriate" manner by the chief executive and, in effect, asked to leave the building.
The DFP officials submitted a report on the affair to the department and expressed concern about the health of the chief executive and the potential impact his alleged behaviour might have upon junior staff if repeated.