The Catholic Archdiocese of Los Angeles, after years of legal battles, has released files on priests accused of molesting children.

Archbishop Jose Gomez said he had stripped his predecessor, retired Cardinal Roger Mahony, of all public and administrative duties.

He also removed a top clergyman who had been linked to efforts to conceal the abuse.

Cardinal Mahony's former top aide, Thomas Curry, stepped down as bishop of Santa Barbara.

"I find these files to be brutal and painful reading. The behaviour described in these files is terribly sad and evil," Archbishop Gomez said in a statement.

"There is no excuse, no explaining away what happened to these children. The priests involved had the duty to be their spiritual fathers and they failed," he said.

A spokesman for a victims' support group said that the removal of the former cardinal and bishop was long overdue and a small step after the church spent years fighting to protect them.

"Hand-slapping Mahony is a nearly meaningless gesture," said David Clohessy, director of the Survivors Network of Those Abused by Priests, or SNAP.

"When he had real power, and abused it horribly, he should have been demoted or disciplined by the church hierarchy, in Rome and in the US. But not a single Catholic cleric anywhere had the courage to even denounce him. Shame on them," he said.

The 12,000 pages of files have been made public more than a week after church records relating to 14 priests were unsealed as part of a separate civil suit, showing that church officials plotted to conceal the molestation from law enforcement as late as 1987.

Those documents showed that Cardinal Mahony, 76, and Bishop Curry, 70, his top adviser, both worked to send priests accused of abuse out of state to shield known molesters in the clergy from law enforcement scrutiny in the 1980s.

They also tried to keep priests sent away to a Church-run paedophile treatment centres from later revealing their misconduct to private therapists who would be obligated to report the crimes to police, the documents showed.

Among the documents released was the personnel file of Fr Jose Ugarte, which contains a 1993 letter to an archdiocese official from a man whose name was redacted and who wrote that Ugarte began sexually abusing him in 1983 when he was 17.

A document in the file says that in 1994, then-archbishop Mahony and Fr Ugarte reached an agreement requiring the Spanish priest to "leave the United States and take up permanent residence in Spain" and not to return without the express consent of the archbishop of Los Angeles for seven years.

The final outcome in that case was not immediately clear.

Patrick Wall, a former priest who is a consultant for plaintiffs and prosecutors in Catholic sex abuse cases, said the documents suggested that Mahony had been trying to avoid a public legal case against the priest.

"The important thing is those kinds of documents have never been produced before," Mr Wall said.

Los Angeles prosecutors have said they will review and evaluate the documents, this batch of which includes 124 personnel files, 82 of which have information on allegations of sexual abuse, according to the archdiocese.

The Los Angeles archdiocese, which serves 4m Catholics, reached a $660m civil settlement in 2007 with more than 500 victims of child molestation in the biggest such agreement of its kind in the nation, and Cardinal Mahony at the time called the abuse "a terrible sin and crime".

Victims' advocates have accused church leaders of continuing to obfuscate their role in the scandal, and cite the newly released confidential letters and memos as a "smoking gun" proving complicity by the Cardinal and others.