The author of the report into child abuser John Smyth says police should be considered when it comes to further investigating the extent of the Church of England cover-up.
Keith Makin, a former director of social services, said the Church had been "marking its own homework" and had "not been effective in bringing about change" when it comes to safeguarding.
The Makin review, published this month, concluded that Smyth was the "most prolific abuser to be associated with the Church of England".
Speaking to Channel 4 News about how the report had been received, Makin said:
"There are two things I wanted the report to achieve, and one is to get the victims’ message across firmly... and also to have an impact and to help to bring about change within the church procedures."
The Archbishop of Canterbury Justin of Welby has formally resigned following the scandal and will step aside from his official duties by January 6th – the Day of Epiphany.
But other bishops and senior church leaders have also been implicated in the failure to bring Smyth to justice before he died in 2018.
"The Church is marking its own homework... I think Church officials have been aware of the issues I’ve been raising," Makin said.
"They’ve looked at those issues, but they have not been effective, in my opinion, in bringing about change."
The Bishop of Ely, now Lincoln, Stephen Conway was one named in the Makin Report and labelled as being in "a potentially powerful position to explore concerns about Smyth further, to reinforce the referral to South Africa, to ensure that a police referral had been made".
The Bishop of Lincoln admitted he had received a report about John Smyth while he was in office. In a diocesan statement, he said:
"Once it became clear that there was an international dimension ...I made a detailed disclosure to Lambeth Palace and contacted the relevant diocese in South Africa to alert them to the issue.
"It was my understanding that this matter was reported to the Police in Cambridgeshire and duly passed on to the Police in Hampshire where the abuse had occurred."
The report did not call for the resignation of Stephen Conway.
Keith Makin conceded that the years Smyth was active covered a large span of time and it would be difficult to point to a particular date when the police should have been called, but added:
"I think that there needs to be consideration given as to whether police action needs to be taken."
Makin has been a Director of Social Services, a Chief Executive of an independent childcare company and the Director of a Local Government Improvement Agency.
He has led a large number of abuse inquiries and reviews for both children and adults.
John Smyth was a barrister and serial abuser and a Christian summer camp leader who operated in 1970s and 80s.
He brutally beat and physically abused over a hundred boys and young men in the UK, Zimbabwe and potentially other African countries.