Darren Hughes has stood down as Labour's education spokesman and chief whip as controversy swirls around a sex complaint made against him by an 18-year-old male.

The development was just announced by Labour leader Phil Goff, who said he had asked Hughes to stand down from the key roles after details of the allegations, which concern an early morning incident in Wellington, were made public.

Goff said Hughes had agreed to the move.

He said Hughes would remain in Parliament while the investigation continued.

"There is now a public controversy around the complaint. I believe that that makes it impossible for Darren Hughes to do his job.

"As a consequence I've made a decision and Darren Hughes agrees that he should stand down from his role as spokesperson on education and chief whip pending the outcome of this police inquiry. He is staying in Parliament at this point."

Goff also defended his handling of the issue, including his decision to not go public with details of the complaint when he first learned of it about two weeks ago.

"When I first heard about the complaint that had been lodged against Darren Hughes, I made a judgment that it would be unhelpful for me to go public on that information.

"Firstly, it would not help a police inquiry that was taking place, because there'd be a storm of controversy around it. Secondly, it would not help Darren Hughes himself, who is innocent till prove guilty and thirdly it would not help the complainant.

"I think that was the right judgment to make."

GOFF: LEADERSHIP 'NOT EVEN AN ISSUE'

Goff was sure his leadership was not being questioned from inside the Labour party: "because I know my caucus."

"I don't think that's even an issue."

However, the party's MPs have not met to discuss the affair. "But I have talked to many of my colleagues."

"They are really upset that this has occurred and the damage that that might do to Darren's career."

David Shearer will take on the education spokesman role and Steve Chadwick will take over as chief whip.

Goff said it was "unfortunate" for Hughes. "This damages his future career and he would acknowledge that."

HUGHES LEAVES WELLINGTON

Goff talked to Hughes today and they were unable to determine when the police might complete their investigation. Hughes is understood to have left Wellington.

Hughes had agreed it was too difficult for him to continue in his roles as chief whip and education spokesman, Goff said.

"He said he would do whatever is the appropriate thing for the interests of the Labour party."

Goff said he believed Hughes had integrity. "But the decision about the complaint and the substance of the complaint is not mine to make. I don't know all the facts, it's for the police."

Asked if Hughes had displayed the judgment expected of a member of his caucus, in taking an 18-year-old back to Annette King's house, Goff said he would wait for the outcome of the inquiry to make a decision.

Asked if Hughes expected to return to his roles, Goff said: "Mr Hughes said he is prepared to do anything that is appropriate for the party. I think that is an entirely honourable thing for him to do.

"He understands the seriousness of the situation, he believes he has done nothing wrong."

He said he was very disappointed the situation had arisen, but wouldn't answer if he was disappointed in Hughes.

GOFF: I GOT WORTH CASE WRONG

Goff also admitted he made mistakes in his handling of the Richard Worth complaint - where he demanded Prime Minister John Key reveal details of a complaint against the former Internal Affairs Minister, which saw him quit in 2009.

"I think I've learnt one or two things about the complexity of these situations. I am going to be the first to admit that I was wrong in the judgment that I made at that time.

"People are entitled to be regarded as innocent until they are proven guilty and Darren is entitled to that presumption."

He said he had to wait until the police inquiry was complete before making any further decisions.

"I believe I got in wrong in hindsight," Goff added.

FUTURE IN DOUBT

Labour MPs have been backing Hughes, but there are questions about whether his political career can survive the controversy, with one senior party source confirming his future was likely to be reviewed regardless of whether charges were laid in relation to the alleged incident.

Hughes is one of Labour's rising stars, but his ability to remain in politics is under a cloud after it was revealed police were investigating a sex complaint from an 18-year-old male.

Hughes said in a statement yesterday that he had done nothing wrong.

He could not be contacted this morning, but is said to be determined to clear his name and continue in politics.

Labour MPs said they were standing behind Hughes, but none were prepared to comment on whether he could survive the controversy.

Junior whip Steve Chadwick said Hughes had "huge support" in the caucus.

"We all respect him as a colleague enormously."

She would not comment on whether the investigation had damaged Hughes or whether his future was in doubt.

Labour list MP Maryan Street said Hughes had her "unqualified support" but would not comment on what might happen after the investigation.

Hughes has been sent a message of support from Labour's Otaki electorate chairwoman, Jan Nimmo, who said her only knowledge of the police investigation was what had been publicly reported.

"I have sent a message of support personally. I'm not making any more comment."

The committee had not met over the issue and had no current plans to do so.

Hughes, who held the Otaki seat from 2002 until he lost to National's Nathan Guy by 1354 votes in 2008, has already been selected as Labour's candidate.

But one senior source indicated that though Hughes was clear that he had done nothing wrong and the party's hierarchy were standing by him during the investigation, his future was likely to be reviewed once it was completed.

Another senior source said the issue was a major test for Phil Goff's leadership, and it was inevitable that he would have to consider Hughes's future regardless of what the police decided.

"This is an issue that Phil will have to lead on and he'll have to take those decisions and take them promptly."

Some Labour figures have said privately that they do not think Hughes can survive the controversy.

Political marketing expert Claire Robinson said if Hughes was cleared of wrongdoing his political career could survive but he would have to weather the personal embarrassment.

"Just like Shane Jones survived being caught out looking at porn on the taxpayer.

"They have to just weather the storm, really. Their image will always be tarred with this, whether they're innocent or not."

However, if it dragged on, Goff would have to ask Hughes to take indefinite leave and if charges were laid, he would have to resign from Parliament.

"Even if he decides that he is not guilty and wants to fight it then that's a really big distraction that Labour doesn't need in election year, and it's long and it could be really embarrassing and a whole lot of things could come out."

THE COMPLAINT

Police are investigating a sex complaint from an 18-year-old male in relation to an alleged incident in the early hours of March 2.

The incident is alleged to have happened after a university celebrity debate the previous evening as part of Orientation Week. Mr Hughes was a guest speaker at the debate.

He, the complainant and several other people then went to several Wellington bars, including the Matterhorn and The Establishment before Hughes and the complainant ended up at the home of Labour deputy leader Annette King, where Hughes stays while in Wellington.

One source said the complainant left King's home some time after arriving there and walked into the path of a passing police car.

Police investigating the boy's complaint searched King's home for evidence.

A source close to the complainant said he was bearing up well, but his parents declined to comment.

Police are understood to have interviewed Hughes several times and have also spoken to a large number of people who were there that night.

Police today said they would be making no further comment while the investigation continued.