The media outlet that revealed New South Wales Labor MP David Campbell's hidden sexuality is defending its decision to air the story.

Mr Campbell quit in dramatic circumstances on Thursday night, just minutes before he was shown on Channel Seven walking out of a gay sex club in Sydney's east.

His resignation forced Premier Kristina Keneally to make a hasty Cabinet reshuffle.

Mr Campbell had not breached any of his ministerial responsibilities by visiting gay club Ken's at Kensington, although Ms Keneally said the fact that he used his ministerial car to get there was inappropriate.

Ms Keneally said Mr Campbell stepped down because he was backed into a corner.

"It's a resignation I accepted on compassionate grounds," Ms Keneally said.

"Clearly he needs time for himself and for his family to work through what is unquestionably a very difficult period for him personally, for his family.

"And can I say that I do think it is a matter for debate whether or not a person's sexuality is of relevance to their role as a minister."

Channel Seven said it was right to broadcast the story because the minister's private conduct was at odds with his public persona.

Seven's news director Peter Meakin says Mr Campbell has been hypocritical.

"I think you've got to look at the aspects that apply in each case," he said.

"In the case of Mr Campbell, here was a guy who had been minister for police, which is a very sensitive portfolio, who had been presenting himself and gaining re-election as a happy family man - sending out Christmas cards with his wife and sons pictured on the card and portraying himself as a loving father and husband.

"Now all this time and apparently for the last 25 years he has been acting otherwise. I think the electorate have the right to know that."

Christmas card

But Dr Simon Longstaff from the St James Ethics Centre says that is a weak argument because Mr Campbell did not make his political career campaigning on moral issues.

"It doesn't seem to be true that it holds for David Campbell, who ... has done nothing more than be truthful about the fact that he has a family," he said.

"I mean, you might think that using one's family to promote a political career has all sorts of problems.

"But as far as I know, David Campbell is married, he does have a family and he has indicated that in his Christmas card because that is part of who he is.

"I mean he is obviously a complex person. But to say that he has engaged in some kind of gross act of political hypocrisy is to make too great a statement in relation to this particular case."

Mr Meakin says the story is best justified by its subject.

"But at the end of the day, if we want any endorsement for what we have done, I quote Mr David Campbell who says, 'I apologise to my wife, family, colleagues, staff and the community for letting them down'," he said.

Mr Campbell is not alone in his dilemma. The Gay and Married Men's Association (GAMMA) says it receives tens of thousands of calls a year from men who are struggling with their sexuality.

GAMMA spokesman Greg Smith says the story is a sad reflection of the media at its worst and it will be a worry to people who are coming to terms with being gay.

"Many people come to organisations like GAMMA because it is discreet and private and the matters that are discussed in the organisation stay there," he said.

"For these people to now know that somebody with a wandering camera could photograph them and then make it known to other people what is going on in their private life sends off a completely wrong message to these people who we are trying to encourage to come to grips with their own sexuality."

Talkback views

Mr Campbell is a sitting member in the seat of Keira in Wollongong where talkback lines have been running hot.

Callers' anger was directed at both the former minister and the media.

"I am seething with anger; not at what David Campbell did but the way the people who were filming it had gone about it," one caller said.

"I think if you are a member of parliament, don't you have to be of good character, of good rapport and honest, which he in this instance has not been honest with his family," another said.

"Basically it's homophobia and I think the best thing for him and his family is to stand for Keira. I don't vote Labor but I will if he stands," another caller said.

Mr Meakin insists Channel Seven has acted appropriately.

"When it comes to handing out Walkley Awards, we probably won't get one for this," he said.

"Am I proud that we have done the story? Yes, I am."

Ms Keneally says the media's conduct will be the subject of debate, but it is important not to forget that there is a human toll in this story.

"Let's just all have a deep breath and understand what has happened here," she said.

"A man who has been living with a secret about his sexuality for over two decades has had it come out, not in the manner of his choosing and certainly in a way that is most devastating for his family.

"I think we all just need to recognise the complexity of this situation."