A review of how the Church of England dealt with two paedophile priests contains significant inaccuracies, a BBC investigation has found.
The review, carried out by Baroness Elizabeth Butler-Sloss for the Church, looked at how historic claims of abuse by two Sussex priests were handled.
Evidence obtained by BBC South East appears to show a bishop provided incorrect information to the inquiry.
The Church said the new information did not undermine the review.
Roy Cotton and Colin Pritchard abused children in the 70s and 80s. Pritchard admitted the crimes in 2008. Cotton had a conviction dating back to the 1950s.
Cotton was ordained in 1966, despite having a conviction for indecently assaulting a choir boy. He went on to abuse at least 10 boys from Eastbourne in the 70s and 80s.
In 1999, the year when Cotton retired as a priest, Bishop Wallace Benn gave him permission to continue with his priestly duties.
The bishop appears to have told Baroness Butler-Sloss that he was not concerned about granting the permission, because of Cotton's continued ill-health and because he had a lack of contact with children.
But the Reverend Val Gibbs told the BBC that Cotton was still active and working in three churches with access to children.
She said: "On the two occasions that I met him, actually in the church, he was celebrating the Eucharist, and preaching."
Ms Gibbs said there were children present at the time.
Bishop Benn also appears to have told Baroness Butler-Sloss that the purpose of the permission to officiate, issued in 1999, was to permit Cotton to celebrate Communion in the nursing home where he was then living.
The BBC discovered Cotton was not living in a nursing home in 1999.
On Valentine's Day 2002, he conducted a wedding at Sedlescombe Church in East Sussex.
He was not admitted into a nursing home until September 2003, four years later than the report states.
The BBC sought clarification from the Diocese of Chichester and was told that Cotton went into the nursing home around 2001.
The Reverend Duncan Lloyd James, who took over from Cotton, spotted the inaccuracies.
The former Rector of Brede with Udimore said: "The significance is that the hierarchy in the diocese was saying it doesn't matter that he has his permission to officiate because he's only in the nursing home, only ministering there.
"Indeed Baroness Butler-Sloss says that there's no evidence that he was ministering anywhere other than in the nursing home.
"But that isn't true, he wasn't even in a nursing home for the first three or four years after his retirement."
Evidence uncovered in the BBC probe found Cotton was living in a bungalow in Sedlescombe - in the same village where fellow paedophile priest Pritchard lived and worked.
After the inaccuracies came to light, Phil Johnson, one of Cotton's victims, said: "I think the Butler-Sloss report is completely discredited.
"I mean there are so many errors in it now that have been clearly demonstrated by the BBC's investigation that I think it's lost all credibility."
And another victim of Cotton, who has remained anonymous, said: "I'm not sure what I can believe.
"I don't even know if I can believe any of the Sloss report now.
"If there's errors, mistakes, cover-ups, whatever you want to call them, just one, do I believe the rest? I really don't know."
A spokeswoman for the Diocese of Chichester said new information had come to light since the publication of the report which drew into question the claim that Cotton was in a nursing home in 2001.
She said: "It now appears that Cotton did not formally move to a nursing home until 2003, although he was ill during the years 1999 on and may have spent some time in hospital.
"What is also now clear is that there were periods between 1999 and 2003 where he was sufficiently healthy to be able to minister in parishes, and we have verified a number of dates."
But she added: "This correction does not, in our view, undermine the credibility of the Butler-Sloss report.
"Rather, it only underscores one of that report's conclusions, which was that the failure to remove Roy Cotton's permission to officiate in May 2001, when his conviction for indecent assault in 1954 came to light, was a serious error."
She continued: "The diocese has already apologised in full for that error, but wishes to acknowledge that this new information demonstrates even more strongly how important it is to get these matters right."
She said the diocese had previously drawn attention to a statement in the Butler-Sloss report about her difficulty in verifying some of the factual information, because of the poor standard of record-keeping at the time, and the consequent need to rely upon memory.