Anthony Critchley, 66, of Sandby Court, Chilwell, was charged with six counts of indecent assault on a child and one of committing a gross act of indecency towards a child.
The offences were committed whilst off-duty in the early 1970s against three boys in their early teens.
Nottingham Crown Court heard how Critchley abused the boys at Attenborough Nature Reserve and other locations during the 1970s.
Two of the survivors came forward after seeing articles published by Nottinghamshire Police and the Nottingham Post when Critchley was jailed for two years, in 2016, after being found guilty of non-recent sexual offences.
They said they were ‘haunted’ by their experience at the hands of Critchley and one of the survivors said he hadn’t told anyone about the abuse until he came to see the police at Christmas 2016 because he felt he couldn’t tell anyone about it.
Critchley, who retired from the force in 2001, was jailed for 28 months, was made subject of a 10-year sexual harm prevention order and must sign the Sex Offenders’ Register for 10 years.
Detective Chief Inspector Rob Severn, of Nottinghamshire Police said: "Today’s sentencing is testament to the bravery of the victims who came forward and trusted the police service with this complaint.
"Critchley was in a position of trust when these offences were committed and he used his position to abuse the children for his own sexual gratification.
"Nottinghamshire Police takes reports of such matters seriously and investigate them, working with the Crown Prosecution Service to put a robust case to the courts. Reporting of such matters should not be deterred by time delays or the community standing of those responsible.
"Critchley’s sentencing will never make up for what happened but I hope it gives the survivors some comfort to know that he has been locked up for a significant amount of time.
"I also hope this sentence gives encouragement to any other survivors of abuse that they can come forward and we will investigate and seek justice for them - even if the abuse happened a long time ago."
There are a number of different agencies who are able to offer independent help and support to survivors of sexual abuse in Nottinghamshire.
More information on these services and details on who to contact if you have been a victim of a sexual offence can be found by visiting https://www.nottinghamshire.police.uk/advice/