The former Conservative prime minister Sir Edward Heath would have been questioned over allegations he raped and indecently assaulted boys were he alive today, according to an investigation.
Wiltshire Police said seven historic claims spanning from 1956 to 1992 would have been sufficiently credible to justify interviewing the late MP for Old Bexley and Sidcup under caution.
Police said the £1.5m operation, codenamed Conifer, only aimed to assess whether there would have been enough evidence to question Sir Edward, who was prime minister between 1970 and 1974. He died aged 89 in 2005.
Police said none of the allegations took place while he was Prime Minister.
“No inference of guilt should be drawn by the decision to interview under caution,” a spokesperson said.
“The account from Sir Edward Heath would have been as important as other evidence gathered as part of the wider investigation.”
They include the alleged rape of an 11-year-old boy, indecent assault of a 10-year-old boy and the indecent assault of a 15-year-old boy during three “paid sexual encounters”, and are said to have occurred between 1961 and 1992 in London, Kent, Sussex, the Channel Islands and Wiltshire.
Chief Constable Mike Veale said there were “compelling and obvious reasons to investigate” the allegations.
“Sir Edward Heath was an extremely prominent, influential and high-profile person who was arguably one of the most powerful people in the world,” he added.
“I hope people will understand that, given these circumstances, it would be an indefensible dereliction of my public duty as a Chief Constable not to have investigated such serious allegations against a former Prime Minister, even though he is deceased.”
He added that children and adults who say they have been abused “deserve to be listened to and taken seriously”, and must have confidence in the police.
He also said the report was a “watershed moment” for those who made claims of an establishment cover-up, with the investigation team concluding there was no evidence.
During the investigation, three people were arrested on suspicion of non-recent child abuse, with two released without charge and the third still under investigation.
Lord Macdonald QC, the former Director of Public Prosecutions, accused Wiltshire Police of “covering their backs” at the expense of a man who can no longer defend himself.
"This gives entirely bogus credibility to their investigation without meaning anything in forensic terms,” he added.
"The bar for interview is low, in most investigations as low as the police want it to be – and in the case of a dead man, virtually non-existent.”
Supporters of Sir Edward condemned police for leaving him unable to clear his name with their open-ended probe.
Lincoln Seligman, Sir Edward's godson, called for a judge-led review into the investigation and heavily criticised the police’s televised appeal for potential victims to come forward
“I don’t believe any of the allegations. I knew him to be a man of great integrity and not so idiotic as to go and jeopardise his career and the things he wanted to achieve himself and for the country by indulging in something so dangerous and pointless.”
Penny Gummer, who was Sir Edward's secretary between 1971 and 1977, said he “had a driver and protection officers, a policeman outside his front door and a housekeeper in his house” and claimed he would not have been able to generate the “unfailing respect” of friends and colleagues if guilty of the alleged abuse.
The Conservative MP for North Wiltshire, James Gray, said Sir Edward “couldn’t possibly have done” what was claimed at times where he was under 24-hour close protection or taking thyroid medication that made him “sexually inactive”.
He added that he would be raising calls for a review in the House of Commons on Monday.
However, a charity supporting victims of child abuse, said it was right for officers to launch a “thorough and proportionate investigation” into claims the politician preyed on children in abuse spanning three decades.
“Far too often in the past, allegations of child abuse against people of public prominence, such as celebrities, politicians, sporting figures, priests or other figures of high standing, were dismissed out of hand, without any proper scrutiny of the claims,” said Gabrielle Shaw and Peter Saunders, the chief executive and founder of the National Association for People Abused in Childhood (NAPAC).
The force called its investigation “impartial and thorough”, stressing its legal duty to look into criminal allegations made against deceased suspects.
It received 42 disclosures relating to 40 people over 14 different police force areas in the UK.
Of those, 19 were found not to meet the threshold for interview, three complaints were withdrawn, 10 were reported by a third party and another three allegations were made anonymously.
The report revealed that there was “reason to suspect” two people may have intentionally misled the police by claiming that they were abused by Sir Edward.
“In the case of one of these disclosures, a live criminal investigation remains ongoing,” it states.
Another person was formally cautioned for wasting police time after admitting that they had misled the investigation by falsely claiming to be three different people in three separate claims.
Operation Hydrant carried out two reviews on Operation Conifer, which concluded that the probe was proportionate and being carried out in line with national guidance.
The report marks the official end of the probe, which was launched in 2015. Its findings will be passed to the wide-ranging Independent Inquiry into Child Sexual Abuse, which is being chaired by Professor Alexis Jay.
Wiltshire Police’s probe has proven controversial since a senior police officer made a television appeal outside Sir Edward's former home in Salisbury in August 2015, urging victims to come forward.
Operation Conifer began as a corruption probe over claims the prosecution of a brothel owner was dropped after threats were made to expose Sir Edward, with Wiltshire Police leading at least seven forces carrying out inquiries into the former Prime Minister.
But in May last year, the probe found no evidence to support the corruption claims involving madam Myra Ling-Ling Forde, who herself said she had no knowledge of misconduct.
Dr Rachel Hoskins, a leading criminologist enlisted by detectives to examine evidence, said she had “exposed a catalogue of fabrication” at the heart of the investigation and warned the force it should immediately end its consideration of key accuser's “pernicious” claims of satanic ritual abuse.
Dr Hoskins branded the inquiry “a disgrace” and said that, while the force had accepted her report, she had “little confidence” police would pass the findings on to MPs.
It came after another high-profile child abuse investigation, Operation Midland, closed without any arrests being made over claims of a VIP paedophile ring after the evidence provided by a sole witness known as “Nick” was discredited.
A raft of politicians from across the political spectrum have been accused of abusing children, including Liberal Democrat Sir Cyril Smith and Labour peer and former MP Lord Janner.