Allan Richards, who was also a Scout master, was branded as posing a 'continuing significant risk of serious harm to the public' as he was sentenced for 40 convictions against 23 boys today.
His crimes included rape and indecent assaults dating back to the 1970s against 23 victims, 17 of which were abused or exploited.
The former West Midlands detective showed no sign of emotion as he stood in the dock at Birmingham Crown Court in front of some of his victims who wept as his jail term was announced.
"It is abundantly clear to me you have been a predator the whole of your adult life," Judge Francis Laird QC said.
"I have no doubt you became a Scout leader to get access to young boys and commit sexual offences against them. You also grossly abused your position as a police officer. Instead of fighting crime and protecting the public you used your position to abuse boys and commit your crimes.
"It is clear your actions have had a damaging effect. I have observed you and you have shown no remorse. I have no doubt if given the chance that you would continue to commit offences against boys. You were entrusted with the welfare of children and the vulnerable. You simply exploited that trust for your own sexual gratification."
Over two trials, Birmingham Crown Court was told the defendant, now aged 54, sexually abused boys at police stations, at Scout camps, in swimming pools, in a park, at his home, and other locations that cannot be disclosed.
Children's charity the NSPCC today highlighted how West Midlands Police had missed previous opportunities to bring Richards to justice.
"Richards not only used his roles as police officer and scoutmaster to subject vulnerable boys to sickening abuse - he convinced many of them that no-one would believe them," spokesman Adam Burling said.
"In the light of this, it is deeply concerning that West Midlands Police has admitted opportunities may have been missed to bring Richards to justice in the early 2000s. But it is right that the force has referred itself to the IPCC to look in detail at the investigation.
"It takes tremendous bravery for a survivor of abuse to speak out. So it is absolutely vital they can do so in the knowledge they will be taken seriously, no matter how many years have passed or who their abuser was.
"Richards has now faced justice, which could not have happened if his victims had not come forward."
Victims of abuse can contact the NSPCC helpline in confidence, 24 hours a day seven days a week, on 0800 808 5000 or via firstname.lastname@example.org.
Children can contact Childline on 0800 1111 or at www.childline.org.uk.
Some of his victims were from troubled backgrounds and already victims of sexual offences.
During a search of his home in Thaxted Road, Tile Cross, Birmingham, detectives found a list of 35 male names Richards had a 'sexual interest' in.
They also discovered diaries where Richards kept details of 'touching' boys as well as describing their underwear.
Checks also showed he used the force computer to 'keep tabs' on his victims, with these searches representing 25 per cent of all his 8,000 pages of inquiries into the database.
It is believed there are more victims police have been unable to trace.
He escaped prosecution in 2000 and 2004 following complaints to police but both times no action was taken.
He went on to abuse six more victims.
Miss Miranda Moore QC, for the prosecution, said: "The defendant set out to meet and groom young boys in a variety of ways. Not only did he use his position as police officer to abuse vulnerable boys, he also used his position as a Scout leader to get access to a wider number of boys.
"He is a continuing danger to young boys. It is not just his over 30 years of offending but because when he was a police officer he carried on offending not once but twice after complaints were made in 2000 and 2004.
"It was a deliberate abuse of his position as a police officer to facilitate offending and prevent reporting - a number of the young boys said he told them no one would believe them."
She read extracts from some of the victims who said they felt 'ashamed' and had 'confidence and trust' problems.
Richards was ordered to pay £60,000 court costs and banned from contact with children and entering swimming pools. He will remain on the sexual offenders register for life.
The offences were broken down into three strands meaning he will serve nearly 13 years behind bars before being considered for release.
Once freed he faces being on licence for the remainder of his 22 year sentence plus an additional five years on top.
The police watchdog has launched an investigation into how he escaped being charged before.
Assistant Chief Constable Alex Murray branded the offences as the 'ultimate betrayal' and described Richards as a 'predatory paedophile'.
Richards retired with a full police pension in 2011 and had spent time working in CID in Birmingham investigating serious crimes and dealing with vulnerable witnesses.
But a fresh investigation was launched in 2014.
Richards had his leader's warrant removed by the Scout movement in 2004 following allegations on sexual abuse against a boy at a camp.
Despite no further action being taken the Scout Association refused to lift the suspension of his warrant and he was banned from being involved with the organisation.
In 2005, Richards was moved to a back office role with the police where he would have no contact with the public.
In total he was found guilty of two rapes, 20 indecent assaults, seven cases of sexual activity with a child, three instances of gross indecency, one count of inciting sexual activity with a child, one charge of a serious sexual assault, five counts of misconduct in public office, and one charge of voyeurism.
He was acquitted of one rape, four charges of indecent assault, and 11 counts of sexual activity with a child.
Richards denied all 56 charges against him and has launched an appeal.
He faces being stripped of 60 per cent of his police pension.