A series of accusations have been levelled against John Smyth, a former leader at the Iwerne camp, which had close links with the Church of England and where Justin Welby worked as a dormitory officer in the late 1970s.
Mr Welby has insisted he was ‘completely unaware’ of the allegations after the Church issued an apology over its handling of the claims.
The allegations have come to light following a Channel 4 News investigation into the prominent QC and part-time judge, who is now based in South Africa.
The Iwerne Trust, which oversaw the Christian camps, was made aware of the allegations and compiled a report in 1982 but failed to tell police, Channel 4 News said.
Although not naming Mr Smyth, Hampshire Police have confirmed they are investigating ‘a senior figure at the Iwerne Trust’.
A statement said: ‘We are investigating allegations of non-recent physical abuse involving a senior figure at the Iwerne Trust.
‘We have contacted those victims whose information has been provided to us and we would encourage anyone else with any information about these events to contact our dedicated investigation team via 101, quoting Op Cubic.’
Asked about the allegations, Mr Smyth told the broadcaster: ‘I’m not talking about that.’
A statement issued on behalf of Mr Welby said: ‘John Smyth was one of the main leaders at the camp and, although the Archbishop worked with him, he was not part of the inner circle of friends; no-one discussed allegations of abuse by John Smyth with him.’
It went on: ‘We recognise that many institutions failed catastrophically but the Church is meant to hold itself to a far, far higher standard and we have failed terribly.
‘For that the Archbishop apologises unequivocally and unreservedly to all survivors.’
Speaking on LBC Radio today, Mr Welby said he had been ‘completely unaware’ of any allegations when he worked at the camp.
He said: ‘I was at that particular camp in the mid-70s. I was young then - 19 to 21 or 22.
‘I never heard anything at all, at any point.’
Speaking about Mr Smyth, the Archbishop added: ‘I wasn’t a close friend of his. I wasn’t in his inner circle or in the inner circle of the leadership of the camp, far from it.’
Mr Welby said he was first informed of the alleged abuse in late 2013 or early 2014, by which time it had been reported to the police ‘as per the Church rules’.
He added that he had only had fleeting contact with Mr Smyth since.
‘I have a vague feeling I may have had a Christmas card in the 1990s and when I was living in Paris he passed through and I shook hands with him, that was the limit.’
The Titus Trust, which took over some functions of the Iwerne Trust, said it was made aware of the allegations in 2014 and informed police and the Charity Commission.
It said: ‘The allegations are very grave and they should have been reported to the police when they first became known in 1981.’
Public school Winchester College, which had connections with Mr Smyth, confirmed in a statement that it had carried out its own investigation into allegations about him.
It said: ‘Nothing was held back in 1982 in the school’s inquiries. House masters were informed, and many parents consulted.
‘The then headmaster met John Smyth and required him to undertake never again to enter the college or contact its pupils.’
The college said no report was made to the police at the time, partly at the wish of the parents of the boys involved in the allegations.
The statement went on: ‘We do not know whether any pupils or parents, undergraduates or university authorities reported the matter directly to the police.
‘College authorities did their best to deal responsibly and sensitively with a difficult situation, in accordance with the standards of the time.’
It added: ‘The law today is very different from 35 years ago, insisting that any allegation must be immediately reported to the authorities.
‘Winchester College has already been in contact with the police regarding the allegations and will assist further in any criminal investigation.’