A Vatican report has found that two recent popes and Church officials ignored allegations about a US cardinal later found guilty of sex abuse.

Theodore McCarrick, a former archbishop of Washington DC, was expelled from the priesthood after the Vatican concluded its investigation last year.

It has now issued a report into how he was able to rise through the ranks, despite allegations going back decades.

It argues that credible evidence only surfaced in 2017.

The current Pope, Francis, then ordered the investigation and last year Mr McCarrick, now 90, was found to have sexually abused a teenage boy in the 1970s.

His abuses may have taken place too long ago for criminal charges to be filed because of the US statute of limitations.
What did the report find?

The 450-page report includes testimonies and dozens of letters and transcripts from Vatican and US Church archives.

Mr McCarrick served as archbishop of Washington DC from 2001 to 2006.

The report finds that the late Pope John Paul II, who died in 2005, was told of his abuses but chose to believe American bishops who instead concealed the information and Mr McCarrick himself, who denied it all.

It also finds that Pope Benedict XVI, who resigned in 2013, probably rejected the idea of an investigation because there were "no credible allegations of child abuse".

The report acknowledges that, in hindsight, the Vatican's investigations into the allegations against Mr McCarrick were of a "limited nature".

In July 2018, Mr McCarrick became the first person to resign as a cardinal since 1927. Pope Francis suspended him from all priestly duties the following February.

He is among hundreds of members of the clergy accused of sexually abusing children over several decades.

"We publish the report with sorrow for the wounds that these events have caused to the victims, their families, the Church in the United States and the universal Church," said the Vatican's Secretary of State, Cardinal Pietro Parolin.

A litany of Church cover-ups
Analysis box by Mark Lowen, Rome correspondent

Two years of investigation, interviews with 90 witnesses - some stretching to 30 hours - and the result: a damning litany of cover-ups and complicity that ignored the open secret of Theodore McCarrick's serial sex abuse and enabled his hallowed rise to cardinal.

It is more than the individuals targeted in this report; it is the entire Church culture under successive papacies that swept facts under the carpet, made denial easy and chose to believe predators over victims.

The fact that the report so candidly exposes the misjudgements of Popes John Paul II and Benedict XVI is unprecedented - particularly the former, who was declared a saint in 2014. Pope Francis is spared the worst of the blame, with the report stressing that he took action with the first claim of paedophilia deemed to be concrete. That previous allegations weren't seen as reliable is an indictment in itself.

Pope Francis has taken some action to tackle the abuse crisis - belatedly, his critics say. But that such crimes could fester for so long is a tragic exposé of decades of failings.

What are the allegations against McCarrick?

He is alleged to have assaulted a teenager in the early 1970s, while working as a priest in New York. The claims were made public by the current Archbishop of New York, Cardinal Timothy Dolan.

Cardinal Dolan said an independent forensic agency had investigated the allegations. A 2018 review board, including legal experts, psychologists, parents and a priest, then found the allegations "credible and substantiated".

At the time, Mr McCarrick said he had "no recollection of this reported abuse" and believed in his innocence.

Several men have since accused him of sexual misconduct at a beach house in New Jersey, where he allegedly took them while they studied for the priesthood as adult seminarians. One man said he was assaulted while still a minor.

It also emerged that financial settlements were reached in at least two cases of alleged sexual misconduct involving Mr McCarrick.

They involved "allegations of sexual misconduct with adults decades ago" while he was working as a bishop in New Jersey, bishops in the state told US media.

Last month two Catholic priests went on trial in the Vatican, marking the first time the city state has prosecuted a case of alleged sex abuse.

While scores of priests have faced abuse charges around the world, the Vatican has never held a trial condemning allegations of sexual abuse within its own walls.

Pope Francis called for "decisive action" when he was elected in 2013, but critics say he has not done enough to hold to account bishops who allegedly covered up sexual abuse.

In August 2018, he wrote to all Roman Catholics condemning clerical sex abuse and demanded an end to cover-ups.