A jury has been sent out to consider whether a former prison officer inflicted sexual and physical abuse on young inmates at a detention centre in the 1970s.

Prosecutors said Alexander Flavell, 89, worked at Medomsley Detention Centre near Consett, County Durham, which was operated in such a way that there was “almost an abusers' charter”.

Flavell has denied that he repeatedly assaulted inmates.

He denies misconduct in a public office, buggery, indecent assault and three counts of assault.

Flavell is unfit to stand trial and is not at Teesside Crown Court where the jury has simply been asked to consider if he did the acts as charged.

Summing up the prosecution case to the jury on Friday, Jamie Hill KC said the treatment of inmates by the defendant could not “ever be regarded as reasonable force”.

He said: “This institution had been set up in such a way that, if somebody was so inclined, it was almost an abusers' charter.”

Earlier this week, Mr Hill said Medomsley was run as a detention centre from 1961 to 1987 and although it was operated under the so-called “short, sharp shock” regime, “it was never intended to give officers a green light to assault prisoners”.

The prosecutor said that the teenage “trainees” had committed offences and were there to be punished but Flavell, whom they nicknamed “Fatty”, persistently exploited his position of authority.

He said that other Medomsley officers committed serious acts of violence and sexual offences and there was an “atmosphere of fear and violence throughout this institution”.

The defendant at times worked as a chef along with Neville Husband, who was convicted of serious sexual offences in 2003 and 2005 and has since died, Mr Hill said.

Flavell, who joined the prison service after 12 years in the armed forces, is accused of buggery – which would now be charged as rape – by attacking a trainee in the hospital unit in 1971.

The elderly defendant is also accused of indecently assaulting a different trainee in the kitchens with Husband in 1972.

Mr Hill said the teenager was forced to strip naked, covered in grease and was repeatedly pushed and pulled through a kitchen serving hatch by the two officers.

Another complainant, who has since died, said Flavell broke his arm in the gym by repeatedly smashing it against a wall.

Caroline Goodwin KC, defending, told the jurors that they cannot be sure Flavell did what is alleged given the inconsistencies in the evidence which cannot be resolved after so much time.

Ms Goodwin said: “What is consistent is the number of inconsistencies across the board.”

She told the jury that evidence that they have heard “is not good enough” to prove her client did what is alleged.

The jurors were sent home by Judge Howard Crowson on Friday and will continue their deliberations on Tuesday at 10am.