VATICAN CITY — There was a time when a Vatican trial could end with a heretic being burned at the stake. Paolo Gabriele doesn't risk nearly as a dire fate, but he and the Holy See face a very public airing over the gravest security breach in the Vatican's recent history following the theft and leaking of the pope's personal papers.

Gabriele, the pope's once-trusted butler, goes on trial Saturday, accused of stealing the pope's documents and passing them off to a journalist — a sensational, Hollywood-like scandal that exposed power struggles, intrigue and allegations of corruption in the highest levels of the Catholic Church.

Gabriele is charged with aggravated theft and faces six years in prison if convicted by the three-judge Vatican tribunal. He has already confessed and asked to be pardoned — something most Vatican watchers say is a given if he is convicted — making the trial almost a formality.