Sexual abuse of minors was rife among superiors of the Legionaries of Christ Catholic religious order, with at least 60 boys abused by its founder, Father Marcial Maciel, a report by the group showed.

The report is important because for decades until 2006, including during all of the pontificate of Pope John Paul, the Vatican dismissed accusations by seminarians that Maciel (photo) had abused them sexually, some when they were as young as 12.

The order said the report, which was released on Saturday and covers the period since Maciel founded it in his native Mexico in 1941 to this year, was "an additional attempt (by the Legionaries) to confront their history".

Maciel, who died in 2008, was perhaps the Roman Catholic Church's most notorious paedophile, even abusing children he had fathered secretly with at least two women while living a double life and being feted by the Vatican and Church conservatives.

Cardinal Angelo Sodano, 92, who was secretary of state under John Paul, was for years one of the Legionaries' biggest protectors in the Vatican.

Pope Francis accepted his resignation as dean of the college of cardinals on Saturday and simultaneously changed church law to limit the dean's position to a five-year term, rather than for life.

The Vatican first acknowledged Maciel's crimes in 2006, when former Pope Benedict ordered him to retire to a life of "prayer and penitence". But Benedict resisted calls from some in the Church who said the order should be dissolved because it was toxic to the core.

The Vatican instead took over the order in 2010 and began a process of reform.

The new report says that between 1941 and 2019, 175 minors were victims of abuse by 33 priests in the order. At least 60, or about one-third, were abused by Maciel himself, it said.

Most victims were boys between 11 and 16, it said.

Abuse of power

While the report said the 33 amounted to only 2.44 percent of the 1,353 priests ordained by the order, it said that nearly 43 percent of those who committed the abuse were in positions of authority, making it difficult to report or punish the abuse.

"(Abuse) was linked to the abuse of power and conscience on the part of some who took advantage of their posts to abuse," it said.

Of the 33, six have died, eight have left the priesthood, and one had left the order. Of the 18 who remain members, four have "ministerial restrictions" to keep them away from minors and 14 have no public priestly ministry, the report said.

Seventy-four seminarians studying for the priesthood also abused minors and 81 percent of them were not ordained.

Father Christian Borgogno, a former member of the order, said the numbers of those abused were "clearly unlikely" to be accurate and believed they were much higher.

"It is difficult to think this is anything more than a whitewash of the (Legionaries') image," he said in a tweet, adding the report lacked "independent sources".

After Maciel's death, Vatican investigations found that he had also fathered several children with at least two women, visited them regularly and sent them money. He also used drugs.

Former members have said the order was run like a cult, with rules forbidding any criticism of the founder or questioning of his motives.

They said Maciel gave huge contributions to the Vatican during the papacy of John Paul, who admired the Legionaries' orthodoxy and ability to produce vocations.