Detectives say they are expecting more charges and called for further victims to come forward following one of the biggest investigations by UK police.
While police leading the investigation into attacks at Medomsley Detention Centre say there was no cover up or gang operation in force at the County Durham complex, staff who should have put the care and safeguarding of those serving their time there seized on the chance to dole out violence.
Operation Seabrook was set up by Durham Constabulary in August 2013 to investigate the claims, which were sparked when one man turned to his MP for help.
Since that point, 1,676 men have contacted the specialist team to report allegations about assaults from as far back as the 1960s and up to 1988, when the centre closed.
It led to 32 still-living suspects being identified, with seven then charged and 11 released with no further action.
These individuals have acted on their own volition and purposes and that is evident by the type of abuse they have given out to the inmates.Detective Chief Superintendent Adrian Green
The Home Office centre, near Consett, was designed to take offenders aged from 17 to 21 across the North East and beyond to keep them out of prison and away from the influence of older criminals.
Many inmates were first time offenders and were being detained for minor crimes, with their terms typically running from six to eight weeks.
Additional trials relating to abuse there are expected, with the third now complete at Teesside Crown Court - five of the 71 complainants called as witnesses have passed away, with their statements read out at hearings.
Following the conclusion of the latest trial, Detective Chief Superintendent Adrian Green, of Durham Constabulary, said it was a complex investigation.
He added: “This has been a long piece of work by a number of dedicated people and we are proud of the team that have managed to get to the end of trial three.
“Our investigation continues and I’m expecting further charges on a number of other individuals imminently and we will move forward with those charges to trial number four.
“Now the reporting restrictions are over, if the fact we have got convictions, that we’ve had three trials, that we have had an overwhelming number of people who have had the trust in the investigation team to come forward, if that gives confidence to other people who have suffered abuse in other establishments, not just Meadomsley, then I would urge them to come forward and talk to use about that.
“We will listen to you, we will treat you with confidence and we will investigate the allegations that you make.”
Det Ch Supt Green added: “I don’t think there is evidence of a cover up.
“There’s clear evidence of a number of people in Medomsley who probably hid behind the Government’s policy of short sharp shocks for their own gratification and abused people who were incarcerated.
“These individuals have acted on their own volition and purposes and that is evident by the type of abuse they have given out to the inmates.
“There are a number of examples where people have had to go to hospital with quite significant injuries.”
The force has said other victims may be moved to come forward in the wake of the publicity of the trials.
Reporting restrictions have been in place during the court hearings and mean only the defendants’ names and ages can be revealed.
The seven defendants were split up into three separate trials, with five being convicted and two cleared. Christopher Onslow, 72, was onvicted of misconduct in a public office, three charges of assault occasioning actual bodily harm, one of inflicting grievous bodily harm, and one of wounding. John McGee, 74, was found guilty of misconduct in a public office and assault occasioning actual bodily harm.
Brian Greenwell, 71, was convicted of misconduct in a public office. Onslow, McGee and Greenwell were found not guilty of sexual offences against the young offenders. Kevin Blakely, 67, was convicted of misconduct in a public office by assaulting and abusing detainees, but cleared of causing actual bodily harm and unlawful wounding. Alan Bramley, 70, was convicted of misconduct in a public office by assaulting and abusing prisoners, but cleared of causing actual bodily harm and unlawful wounding. Durham Police said Onslow and McGee have launched appeals against their convictions. David McClure, 63, and Neil Sowerby, 62, were cleared of all offences, including misconduct in a public office, buggery and indecent assault. The five men are due to be sentenced at a later date.
Victims who got in contact with the Operation Seabrook team were offered counselling and were regularly updated by officers as inquiries went on.