Police Commissioner Howard Broad has launched a new criminal investigation into the behaviour of the police's former national manager of professional standards Jon Moss.

Mr Moss now works as a senior investigator for the Real Estate Agents Authority (REAA).

A police officer for 25 years, he resigned last September while he was national manager of professional standards.

Mr Broad said that before, or after, leaving the police Mr Moss appeared to have had a relationship with an official from an agency linked to police.

He would not say which agency that was.

Mr Broad said he was advised about the relationship last night and based on what he was told he launched a criminal investigation, headed by assistant commissioner of specialist operations, Grant Nicholls.

"Information was given to me in the last couple of days and again last night which suggested that there was an unresolved criminal allegation and it ought to be looked at and that's what will happen," Mr Broad said.

"It's a criminal matter, I'll leave it there."

Last year allegations were made to police that the then Superintendent Moss acted improperly in influencing another officer, Mr Broad said.

That allegation was about how to respond in an interview about a use of force matter.

"The matter was investigated by a senior criminal investigator who determined that there was no case to answer."

Mr Moss resigned in September last year as police investigated another accusation against him.

It was reported at the time that he had resigned after his superiors were alerted to an affair he previously had with a constable. He failed to disclose the affair when applying for the headquarters job of enforcing professional standards.

Had he not resigned an employment investigation would have taken place, Mr Broad said today.

The manner in which he was employed by the REAA was a matter for that agency, the police commissioner said.

The REAA is getting an independent legal review into Mr Moss' appointment.

Associate Justice Minister Nathan Guy said that was the right thing to do.

"Employment matters are the responsibility of the board, but as the minister with responsibility for the REAA I want to be reassured that all the proper processes have been followed in this case.

"Today I met with the chair of the REAA and Ministry of Justice officials who briefed me on this case. The REAA has an important role to play in licensing real estate agents and providing help and support for the public. I want to see this good work continued."

REAA chairwoman Kristy McDonald QC said she had asked Wellington lawyer John Edwards to conduct the review.

Authority spokesman Dan Ormond told NZPA that Mr Moss was staying at the REAA and would not be stood down or taking leave while the review was conducted.

Asked if the resignation of REAA chief executive Janet Mazenier was related to Mr Moss' conduct, Mr Ormond declined to comment.

The Dominion Post reported today that Ms Mazenier had quit amid a budget blowout as the authority faces hundreds of complaints. The REAA to date had received 534 complaints, of which 57 determinations had been made. Two complaints had been referred to disciplinary tribunals, but no hearings had been held.

The newspaper reported the legal budget for complaints was too small for the number of complaints received.