Naomi...the dossier was given to Brittan by Dickens many years ago. The existence of this dossier is not now disputed, although Brittan did try to deny that he had received it last year. I am not in any way surprised that it has "disappeared" as it would been of such an explosive nature, that it would almost certainly have been the worst political scandal ever, even more damaging than previous scandals, like the Profumo affair for instance.
By all accounts, the dossier included some names that were already known. Indeed, some of them were subsequently charged and convicted of paedophile activities.
Dickens was somewhat of a loose cannon amongst his Party, and wasn't always taken terribly seriously. But it is my firm belief that the dossier was removed by the security forces and either destroyed, or permanently removed from view. This is exactly what happened to all the evidence that was collected by the two Police Officers that were given the task of investigating Cyril Smith. They were visited by Special Branch and were ordered by the Deputy Chief Constable to hand over their dossier.
I detailed account of this is included in Simon Danczuk's book about Cyril Smith, " Smile for the Camera...the Secret Life of Cyril Smith. I urge you to read this. It exposed not only Smiths paedophilia but his corruption while an MP.
We have Danczuk to thank for bringing up the name of Leon Brittan in last July's session of the Parliamentary Home Affairs Committee. As a direct result of this, Cameron asked the Home Office Permanent Secretary to investigate what had happened to the dossier.
Danczuk is also responsible for starting off the chain of events that eventually saw Chris Huhne imprisoned, as he made an official complaint to Essex Police.