WASHINGTON (AFP) - An association of US Catholics has launched a petition to keep a retired Los Angeles cardinal mired in a paedophilia scandal from taking part in the conclave that will choose the next pope.

The group, Catholics United, is targeting Roger Mahony, who last month was relieved of all church administrative and public duties for mishandling abuse claims against dozens of priests, dating back to the 1980s.

"Cardinal Mahony: Stay Home," the online petition reads. "Your further implication in the church sex abuse scandal and being barred from public ministry in the Archdiocese of Los Angeles should be an indication to you that you should not attend the next Papal Conclave."

According to Catholics United, Archbishop Jose Gomez, who took over from Mahony in 2011, is in favour of Mahony's attending the conclave that will choose a successor to Pope Benedict XVI, who resigned unexpectedly last week.

Mahony, who is now 76, took part in the vote that chose Cardinal Joseph Ratzinger as pontiff in 2005. He took the name Benedict XVI.

And Mahony is theoretically still a member of the conclave made up of 117 cardinals aged under 80 who will meet behind closed doors in the Sistine Chapel until a new pope is chosen.

This month, the Los Angeles archdiocese released files on over 100 clerics accused of sex abuse, as required under a 2007 lawsuit deal, after records were published showing Mahony discussing how to cover up alleged crimes.

In 2007, the archdiocese, then run by Mahony, reached a US$660 million (S$818 million) settlement with about 500 alleged victims. Under the deal, the archdiocese agreed to release the personnel files of clergy accused of abuse.