There is "no evidence" that a police force scrapped a prosecution because the defendant threatened to publicly accuse Sir Edward Heath of sexually abusing young men, the police watchdog has said.
Wiltshire Police were accused of deliberately causing a criminal prosecution to collapse in 1994 to suppress allegations involving the former prime minister.
Brothel-owner Myra Ling Ling Forde allegedly vowed to tell the press that she supplied Sir Edward with males under the age of consent for sex if the trial went ahead.
The Independent Police Complaints Commission (IPCC) launched an investigation into alleged corruption after a retired officer raised concerns.
But the IPCC found no evidence of any threat, clearing the police force of wrongdoing.
Sir Edward, who led the Conservative government between 1970 and 1974, died at home in Salisbury in July 2005, aged 89.
He was linked to historical abuse allegations last year and a number of police forces launched inquiries.
The overall inquiry has cost £368,000 so far.