A disgraced ex-policeman and former Scout leader has been convicted of 40 sex offences against children as young as eight in a catalogue of abuse spanning four decades.
Retired West Midlands Police sergeant Allan Richards twice used his trusted position to lure youngsters to a police station and attacked his first victim when he was running a football team as a teenage Scout leader in the 1970s.
Richards, 54, formerly of Thaxted Road, Tile Cross, Birmingham, was convicted at Birmingham Crown Court on Friday of carrying out nine indecent assaults against six boys aged between 11 and 15 at camps, swimming baths and other locations, between 1982 and 2003.
For the first time it can now also be reported that Richards had already been found guilty earlier this year of a further 31 sex offences against other boys, including two rapes, going back as far as the 1970s.
In all, Richards' prolific history of what the police called his "disgusting crimes" involved 17 victims.
He had denied all the charges at both trials but was condemned by evidence gleaned from his own coded diaries and a computer hard drive containing a list of male names in which he had a sexual interest.
It also emerged that the 54-year-old had avoided prosecution in the past, after being questioned when allegations first surfaced in 2000 and then 2004.
A file was passed to the Crown Prosecution Service at the time but it was felt there was not enough evidence to convict, according to the police.
The force said it "removed him from public contact" in 2004, but he remained with the force until he retired in 2011.
He was also removed from his post with the Scouts.
Richards was told he would not be prosecuted in January 2005.
It was only in 2014 when another victim came forward that a fresh investigation was launched, resulting in Richards' multiple convictions.
The force referred itself to the Independent Police Complaints Commission (IPCC) in May 2015 over its handling of the earlier investigations.
Speaking after the verdicts, Temporary Assistant Chief Constable Alex Murray said West Midlands Police had already written to apologise to all of Richards' victims.
He also accepted there may have been "opportunities missed" to prevent Richards abusing other victims, after the allegations came to light in 2004.
Of Richards' victims, six of them were abused after the police investigation in 2000.
Mr Murray said: "I think if we were able to do a really thorough investigation then there's a chance we could have safeguarded victims in the future.
"That's something the IPCC are looking into."
At his first trial earlier this year, Richards was convicted of five counts of misconduct in a public office, among other charges, in part for using a police computer to research boys' addresses.
That jury was also told that while a detective constable in the 1990s and 2000s, Richards had also twice lured teenagers under false pretences to a West Midlands police station.
He was also found guilty of having sexual activity with a child, a serious sexual assault, three charges of gross indecency, and seven counts of sexual activity with a child.
Jurors also convicted Richards, who kept photographs of naked boys, of voyeurism in connection with a series of incidents at a swimming baths between 2006 and 2013.
In all, across both trials, Richards was convicted of 20 indecent assaults.
One of his victims, who cannot be identified for legal reasons, said the trial had been a "horrible" ordeal, which had turned his life upside down.
He added: "I had to tell my family, who were really upset."
West Midlands Police and Crime Commissioner David Jamieson said the force now had "very serious questions to answer" over why Richards was allowed to remain with the force until retirement.
He has commissioned a public report into what happened.
Mr Murray, speaking to BBC Radio Five Live, said: "In retrospect when I look back at those investigations, yes we took action, yes we spoke to the victims, but could we have done more?
"I think we probably could have done, and that's why we've referred it to the IPCC, so they can do a thorough investigation and maximise our learning."
He added: "I think a lot has changed in UK policing in the last 10 or 15 years, where we take a very wide view in terms of investigations rather than just dealing with what's immediately in front of us.
"And there could have been opportunities that we missed in the early 2000s, which we embraced in 2014."
Of those people who Richards abused, Mr Murray said: "I am genuinely sorry for those people who have been victims of his crimes, they are really disgusting crimes.
"He's not only betrayed confidence in the police, he's betrayed the police service as well."
IPCC commissioner Derrick Campbell said the scale of Richards' offending had been "truly shocking" and an independent investigation into the police's handling of the original complaints was now under way.
He said: "His victims will not be alone in wanting to know if opportunities were missed, and our independent investigation will examine whether more could have been done by the force to uncover his activities sooner.
"We will also seek to establish what lessons can be learned."
Children's charity the NSPCC said: "By denying these offences, he forced his victims to endure the ordeal of a crown court trial and relive the horrors of the abuse he inflicted upon them.
"These cases show that abuse victims will be listened to, no matter how long ago it happened or who their abuser was. They do not need to suffer alone."
Richards will be sentenced on November 4.