The PSNI's Chief Constable has been forced to defend the man responsible for police recruitment after he faced intense questions over the rehiring of officers who retired under the Patten reforms.

The exchanges came as Matt Baggott and his Director of Human Resources Joe Stewart faced the Stormont Justice Committee for the first time.

Mr Baggott apologised after his senior official was accused by Sinn Fein of having wrongly told Policing Board members that rehired officers were accountable to the Police Ombudsman.

Mr Stewart defended his comments after questions from republican MLA and committee vice-chair Raymond McCartney.

But as a further Sinn Fein representative continued to press Mr Stewart, the Chief Constable eventually insisted on answering the questions himself on behalf of the police service as a whole.

Mr McCartney told Mr Stewart: "This does not add to public confidence, that former members of the RUC are in frontline duties and are not accountable to the ombudsman, and you said that they were, in the Policing Board."

Mr Stewart said: "What you read out is exactly what I have repeated, and that is, we expected that they would be accountable to the ombudsman and if they're not prepared to cooperate then they will not be about the place."

The Chief Constable said all police staff were accountable to criminal law and there was no amnesty for former officers who might offend during their current police employment.

But Mr McCartney said he was making a separate point: "There is a history of retired RUC personnel not co-operating with the Ombudsman.

"They are now being rehired back into the PSNI and they find themselves in the exact same position, that they don't have to cooperate if they don't wish to.

"Then you have a senior member of your staff, when they were asked the question: 'Are you saying that all those staff I have mentioned earlier have to cooperate with the Ombudsman?', and he answers: 'Yes'.

"I would have left that Policing Board meeting feeling that all those staff were accountable to the ombudsman."

The Chief Constable said one line from the Policing Board did not reflect the wide ranging discussions held between the board and Police Service of Northern Ireland representatives, but Mr Baggott added: "Can I clarify my position on that as Chief Constable, and I think Joe has attempted his, if there was a confusion around the words, then that is a matter of apology and I am not afraid to say that on behalf of the organisation.

"But I think what we are talking about here is an expectation, organisationally, that people will cooperate with ombudsman's investigations."

Mr Baggott said the question of a legal power to force compliance with the Ombudsman's office was a wider debate which would include not just police, but also law-makers.

The Chief Constable said under the law he could not bar former officers from employment in the police.

"If there was confusion in relation to an answer at the Policing Board, I am very clear about that, we can clarify that answer and I apologise for that," Mr Baggott said.

"But I can't get involved in discussions which are beyond the law and that is not something I would want to do because I want to be impartial."

DUP representatives defended the use of former RUC officers. The committee heard that around one third of the existing police service are officers who had remained in the service when the RUC became the PSNI.

Democratic Unionist MLA Sydney Anderson said attacks on the rehiring of retired officers was being used as an excuse to damage the reputation of the RUC.

Meanwhile the PSNI team said that dealing with the legacy of the Troubles cost the police £12 million each year.

The Assembly committee was told the figure was the combined annual cost of the Historical Enquiries Team (HET), plus police work related to legacy issues.

The Chief Constable predicted Northern Ireland would face a major debate over how it reconciled itself with the past.

He said further funding would be required for the HET to continue its examination of cases from the Troubles.

But he added: "It is not just the financial cost. It is an opportunity cost.

"My major investigation teams are currently spending 50% of their time going back 10, 20, 30 years, rather than thinking of people trafficking and organised crime in the here and now."