Depraved former deputy head teacher Roy Griffiths, 82, is the third person to be jailed as a result of Operation Redstone, an investigation into complaints of abuse at the Lincoln Diocese.
John Bailey, 76, former director of education for the Diocese of Lincoln and Stephen Crabtree, the rector of Washingborough and Heighington until 2014, have also both been given prison sentences for abuse.
Four other people have also been arrested.
Detective Superintendent Rick Hatton, who is leading the operation, today reveals he believes there a number of other victims out there and has made an appeal for them to come forward.
He said: “We have spoken to over 250 people during our investigation. If I’m honest, I think there will be other people who have suffered abuse at the Cathedral School who have yet to talk to us.
“It takes courage for victims of non-recent abuse to speak up. I hope the success we have seen to date in securing convictions may help anyone who wants to talk to us to pick up the phone.
“We are happy to speak to anyone who went to the Cathedral School, whether they wish to make a complaint or not.”
Griffiths, of South Street, Sherborne, Dorset, was deputy head as well as housemaster and choirmaster at the former Lincoln Cathedral School. He was jailed for six years and seven months at Lincoln Crown Court after he admitted six charges of indecent assault against six boys between January 1963 and July 1970.
He left the school in 1970 following a complaint about his behaviour – but the court heard that neither the school nor the Lincoln Diocese passed the matter onto the police at the time.
Bailey, 76, was director of education for the Diocese of Lincoln from 1996 until he resigned in 2002. He was jailed for six years in 2017 after he pleaded guilty to 25 charges of indecent assault – some of which dated back more than 60 years.
And Crabtree, the rector of Washingborough and Heighington until 2014, was jailed for three years in March 2016 after admitting six counts of indecent assault on a 15-year-old girl between April 1992 and April 1993.
Of the other four people who have been arrested, two of them will not be charged while the other two suspects are still under investigation.
Operation Redstone was launched in 2015 to investigate ‘historical claims’ of child abuse at Lincoln Cathedral School and some churches in the Lincoln Diocese, some of which date back to 1958.
The Dean of Lincoln The Very Reverend Christine Wilson said: “The conviction of Roy Griffiths recognises the appalling crimes he perpetrated while in a position of trust and responsibility at the then Cathedral School.
“This case will have brought to the surface profoundly disturbing memories, for the victims of his crimes, their families, and for those who witnessed the abuse of their friends and peers.
“On behalf of the cathedral, I want to say that I am truly sorry that these matters have only now been brought to justice.
“It is deeply shameful that those who were abused have had to spend most of their lifetime dealing with the aftermath of the abuse perpetrated against them.”
The Dean added: “Tragically, for some, justice came too late. The victims and survivors of Griffiths’ horrendous crimes, and the families of those who have died before justice could be served, have shown enormous courage.
“I wish to acknowledge their bravery in speaking out. Their extraordinary resilience has enabled Griffiths to be brought to justice. It is thanks to them that he now has to account for his actions.
“Lincoln Cathedral will continue to support Roy Griffiths’ victims and their families in any way that we can.
“Our team stands ready to support anyone affected by this case or who contacts us about any issue of harm and abuse.
“We promise to listen attentively to their stories, walk alongside them in seeking justice and ensure that their voices are heard.
“We are resolute in our commitment to ensure that Lincoln Cathedral today is a safe place, and to disrupt the conditions in which abuse can happen.””