Lancashire Police chiefs found ‘ no evidence ’ that attempts to bring Cyril Smith ( pictured ) to justice were blocked . A police force accused of covering up Cyril Smith ’ s crimes faced claims of a ‘ whitewash ’ last night after it cleared itself of blame . Lancashire Police chiefs declared they found ‘ absolutely no evidence ’ that attempts to bring the paedophile Liberal MP to justice were blocked . The internal inquiry contradicts claims by retired detectives that key evidence was ‘ locked away ’ and they were silenced . Labour MP Simon Danczuk , whose book about Smith ’ s sordid double life sparked the investigation , last night accused the force of a whitewash . He said there is a ‘ mountain of evidence ’ that Smith was a paedophile and serious failings had allowed him to ‘ get away with his crimes for years ’ . ‘ It is very disappointing that Lancashire Police are unable to accept this and are now trying to rubbish the claims of their own former officers , ’ Mr Danczuk added . ‘ This shows that we haven ’ t learned lessons from the past and a culture of cover-up and denial still persists. ’ The outcome of the inquiry will raise questions over whether it is appropriate for police to investigate themselves in such cases . Yesterday , the independent police watchdog revealed it is overseeing 14 claims of cover-ups and corruption by Scotland Yard in historic sex abuse cases . The London force will also investigate itself . MPs want Prime Minister David Cameron to guarantee police whistleblowers will not be prosecuted under the Official Secrets Act if they come forward . Scroll down for video . They said ex-officers , public officials and spies may hold vital information that could open up suspected powerful networks that protected abusers . Home Secretary Theresa May yesterday insisted spies and police will not face prosecution under the Official Secrets Act if they give evidence to the police or the Home Office ’ s abuse inquiry . MPs want Prime Minister David Cameron ( pictured ) to guarantee police whistleblowers will not be prosecuted under the Official Secrets Act if they come forward . She has invited Justice Goddard , who is leading the inquiry , to seek confirmation from the Attorney General that no charges would be brought . However , when pressed by the Home Affairs Committee , Mrs May declined to extend the protection to whistleblowers who speak to the media or elsewhere in public . Police suspect Smith ’ s activities as a paedophile could be key to unlocking claims of an Establishment child sex ring . The politician abused children at care homes and schools in Rochdale and Manchester . He was also seen at the notorious Elm Guest House , in Barnes , south-west London , where appalling crimes are said to have taken place involving young boys . Jack Tasker , a former Lancashire detective , who led one of three investigations into Smith , said it was stopped because it could have led to the ‘ fall of the Government ’ . Home Secretary Theresa May ( pictured ) insisted spies and police will not face prosecution under the Official Secrets Act if they give evidence to the police or the Home Office ’ s abuse inquiry . He claims his 1969 inquiry into abuse at Cambridge House care home was stalled by Special Branch officers who confiscated his notes and ordered him to forget the matter . ‘ We were under the impression then that they ’ d take the investigation over … but I never heard any more about it , ’ he told Sky News . He added : ‘ Other people were rather worried that if Cyril Smith went before a court , he would open his mouth. ’ Another ex-officer , Tony Robinson , said he had advised Lancashire Police to look at the case file he found locked in a Special Branch safe in the 1970s . ‘ It doesn ’ t surprise me at all that they ’ ve dismissed the claims , ’ he said . ‘ It ’ s an easy way out. ’ A Lancashire Police spokesman said it had referred the matter to the Independent Police Complaints Commission which ‘ determined that a local investigation be carried out ’ . He added that the Constabulary ’ s Professional Standards Department found ‘ absolutely no evidence to substantiate any of the claims ’ .
Lancashire Police had been accused of covering up SmithCyril Smith 's 's crimes . But force bosses face claims of a 'whitewash ' after it cleared itself of blame . They found 'no evidence ' attempts to bring Cyril Smith 's to justice were blocked . Contradicts claims by retired detective that key evidence was 'locked away ' and they were silenced .