Former Vatican treasurer Cardinal George Pell has been sentenced to six years in prison for a string of sexual assaults on teenagers.

Cardinal Pell was found guilty of sexually abusing 13-year-old choir boys 22 years ago in the priests' sacristy of St Patrick's Cathedral in Melbourne, where he was archbishop at the time.

He was convicted of abusing two boys whom he had caught drinking sacramental wine in a rear room of the cathedral in late 1996, as hundreds of worshippers were streaming out of Sunday services.

He was also found guilty of assaulting one of the boys in a corridor more than a month later.

Conviction

He was actually convicted of five offences in December last year, but details of the verdicts were kept secret for fear they would prejudice a second trial he was facing. Those charges have now been dropped.

His convictions were revealed in February.

Sentencing him, Justice Peter Kidd said some of the offences had a "nasty element" and particularly drew on the fact that the victims were abused in front of each other.

George Pell

Justice Kidd said there had been no evidence that Cardinal Pell was impaired in any way during the offences, and that in evidence to the contrary, he had committed the first offences after delivering Sunday solemn mass.

Justice Kidd said: "What you did was so egregious that is fanciful to suggest you may not have fully appreciated it."

He said the decision to offend was "reasoned, albeit perverted."

Social standing

The judge said that as an archbishop, Cardinal Pell was "profoundly revered" and held up as a pillar of the community.

He said Cardinal Pell's moral culpability was "high" and rejected the defence submission that the offences were to the lower end of the scale.

Sentencing him, Justice Kidd acknowledged that the offences were an "isolated incident" and that apart from them, the 77-year-old was of good character.

He said the cardinal was unlikely to reoffend, given he hadn't in the intervening 22 years between the offence and the sentencing, and his notoriety, advanced years, and registration as a sexual offender.

Cardinal Pell has maintained his innocence throughout and filed an appeal, which will be heard in June.