British police investigated allegations of abuse against disgraced late television presenter Jimmy Savile in 1964 but officers ignored evidence and routinely failed to follow up complaints, policing inspectors said Tuesday.
Her Majesty's Inspectorate of Constabulary (HMIC) also warned in Tuesday's report that there remained a "distinct possibility" that police could make the same mistakes in the future.
HMIC found only five allegations and two pieces of evidence in police files on Savile, who is now accused of over 450 sex crimes.
The earliest police record naming the former BBC presenter and DJ in an investigation dates back to 1964, but officers did not follow up on the evidence, HMIC found.
Lawyer Alan Collins, who works for the law firm representing more than 40 of Savile's victims, slammed the police's reluctance to examine the claims.
"Consequently, Savile was able to carry on regardless, duping the country in the process, and the price was paid by his many victims. There is a definite risk that unless policies and attitudes change, Savile will happen again," he said.
HMIC also found a letter dating from 1998, in which an anonymous whistleblower tells Metropolitan Police that Savile was a paedophile.
HM Inspector of Constabulary Drusilla Sharpling said: "The findings in this report are of deep concern, and clearly there were mistakes in how the police handled the allegations made against Savile during his lifetime."
Asked whether such a scandal could still go undetected, Sharpling said it was neither "enough nor correct to say this couldn't happen now".
The report added that "the inconsistencies in approach that the forces have taken mean that there is a distinct possibility that such failures could be repeated."
Home Secretary Theresa May said the report "brings into sharp focus police failings that allowed Savile to act with impunity over five decades.
"While we can never right this wrong, we must learn the lessons to prevent the same from ever happening again," she added.
A Met Police spokesman said that critics should take into account the number of claimants it has interviewed in Operation Yewtree, the investigation set up to examine historic sex-abuse claims.
A police investigation in January concluded that Savile was a predatory sex offender who abused youngsters as young as eight over more than 50 years, hiding "in plain sight" behind his fame and eccentricity to rape and assault victims on BBC premises, in schools and hospitals.
The 1964 claim against Savile contains the first known reference to Duncroft School, the children's home in Surrey, southern England, where Savile is thought to have carried out many abuses.