“The idea is that to safely convict someone, you have to convince the jury and the appeal board,” said Jeremy Gans, a law professor at the University of Melbourne. The judges in Cardinal Pell’s case, he added, did not have a track record of ruling jury judgments unreasonable.

While the Vatican expelled Cardinal Pell from a powerful council of papal advisers in December, it has yet to defrock him. A Vatican spokesman said earlier this year that the church would await the resolution of the appeals process before considering further action.

Prime Minister Scott Morrison said on Wednesday that the cardinal would be stripped of his Order of Australia, an award bestowed on Australians who have demonstrated outstanding service or exceptional achievement.

The trial — which ran for almost five weeks last year, and was preceded by a first trial that ended in a hung jury — rested on the testimony of the single former choirboy. He said that after the Sunday Mass in 1996, Cardinal Pell caught him and another boy in the priest’s sacristy, where he molested the boys and forced his erect penis into the complainant’s mouth.

The second former choirboy, who died in 2014, never made any complaint about abuse to his family or the police. When his mother approached him with suspicions that he had been abused, he denied it had happened.

Lisa Flynn, a lawyer who is representing the father of the deceased former choirboy in a separate civil case, said she had found the defense’s arguments worrisome.

“Some of the things that have been said flies in the face of a lot of the findings of the royal commission and what we know about abuse survivors,” Ms. Flynn said, referring to an investigation of institutional child abuse in Victoria conducted in recent years. “In many cases,” she added, “people take their stories to the grave.”