Since Simon Danczuk highlighted the appalling crimes of Cyril Smith by raising them under privilege in the House of Commons, he and fellow Labour MP John Mann have campaigned vigorously on behalf of those who have had to live with the consequences of historic child abuse.

They have also been dogged in pursuing any cover-up by the establishment.

Danczuk and Mann’s investigations have also had a political angle. They have levelled numerous accusations at Nick Clegg and the Liberal Democrats. For instance, Danczuk clearly thinks Clegg must have known about the allegations around Smith:

Mr Danczuk says the Liberal Democrats have been “defensive, slippery and shifty”. “They are a party in denial,” he said. “I don’t think they’re fit for government. They are a small political party, I find it incredible that they are claiming that they didn’t hear the rumours about Smith.”

Recently, he accused Cameron and Clegg of colluding to cover-up Smith’s abuses. If he has evidence, he has yet to produce any and, if such allegations of conspiracy are unfounded, his remarks must surely border on the slanderous.

Mann has also made unfounded assertions about what the Liberal Democrats must have known:

‘I don’t believe that they knew nothing. The Liberal Democrats need to hold their own investigation into what they knew and what they covered up.’

With typical sanctimony, Michael White, writing in The Guardian, argued:

‘Nick Clegg may have been a child in 1979, but that was no excuse in 1988 (when Smith was knighted) or 2014 to pretend the Lib Dem machine did not know about the allegations. But that goes for everyone else, too – most conspicuously the police, who failed to prosecute Smith and his network despite powerful evidence, and for those in higher authority, including No 10 and Buck House.’

What is not widely reported – or acknowledged by Danczuk, Mann, White etc – is that Clegg has done more than any other party leader to take the issue of historical child abuse seriously. It is clear from The Daily Telegraph that, rather that cover-up Smith’s activities, Clegg has been determined to ensure maximum openness and co-operation:

‘Nick Clegg wrote to every Liberal Democrat MP, Peer and former MP last year urging them to come forward with any information that could help unearth the truth about what happened.’

It’s apparent from his LBC show  that he has also been proactive by instructing comprehensive interviews of former MPs and searches of his party’s archives. Those are not the actions of a party leader seeking to cover-up the activities of a child abuser. That these activities don’t produce the information that Danczuk, Mann and White want doesn’t mean they haven’t been carried out and carried out in good faith.

Since the revelations regarding Smith, allegations have been made about a number of other politicians. They include the Labour MPs Leo Abse, George Thomas and Greville Janner (now Lord Janner, who has strenuously denied the allegations). Conservative MPs Peter Morrison, Leon Brittan, Rhodes Boyson and David Atkinson have also been the subject of equally shocking allegations. Perhaps most shocking of all is the allegation that Conservative MPs were present at the murder of some of those being abused.

There is also mounting evidence of some form of cover-up. Thatcher is said to have known about Smith and Morrison. There are questions emerging over the role of the police. Uncomfortably for Danczuk and Mann, the establishment, at the time of the most substantiated allegations against Smith (from the late sixties and early seventies), was dominated by Labour politicians and sympathetic officials.

Danczuk and Mann are rational, intelligent men. If they are also honest men they must accept the logic of their arguments:

1. Allegations are now encompassing a significant number of Labour and Conservative politicians;
2. To continue to be regarded as being interested in championing the issue, rather than political point scoring, they need to start asking the same tough questions of Ed Miliband and David Cameron.

If Clegg is expected to have known the rumours about Smith, the logic of Danczuk and Mann dictates that Miliband knew the rumours about Abse, Thomas and Janner and that Cameron should have known the rumours about Morrison, Brittan, Boyson and Atkinson. To remain credible, Danczuk and Mann must show they are interested in the issues above party considerations and pursue Miliband and Cameron at least as doggedly as they have pursued Clegg.

What did Cameron and Miliband know? What did successive Labour governments from 1997 to 2010 know? What did Tony Blair and John Prescott know? What did John Major know? Where are the instructions from Miliband? What effort is being made by Labour to quiz MPs of the era or trawl the whips’ black books? At least Cameron instructed his whips to open their books.

But Danczuk and Mann are strangely silent.

Despite accusations around seven Labour and Tory MPs, Danczuk and Mann remain fixated on Smith and the Liberal Democrats. They do not harangue Miliband and Cameron the way they pursue Clegg. They do not encourage the press to pursue them and make the sort of unsubstantiated accusations made against Clegg.

It’s not good enough for Danczuk and Mann to leave these questions to the Goddard Inquiry. That will rightly take its time to examine the evidence in forensic detail, but it will be years before its conclusions are published. To avoid accusations of tawdry party politicking, if Danczuk and Mann have names and evidence regarding other MPs, whether still serving, out of office or deceased, they should make them known now. They should ask the tough questions now.

Ahead of the General Election. However uncomfortable that information is for Miliband, Cameron, Clegg or any political party.

In the end, Danczuk and Mann cannot have it both ways: they cannot accuse people of a cover-up and then not volunteer what they themselves know.

Our politics deserves more than that.

The victims deserve more than that.