Around 50 witnesses could be called to a hearing in March to determine if there is enough evidence for Vatican finance chief Cardinal George Pell to stand trial on sex abuse charges, a court heard on Friday.

The 76-year-old, a top adviser to Pope Francis, is accused of multiple historical sexual offences relating to incidents that allegedly occurred long ago.

He is the most senior Catholic cleric to be charged with criminal offences linked to the church's long-running sexual abuse scandal.

The exact details and nature of the allegations against Pell have not been made public, other than they involve “multiple complainants”.

A frail-looking Pell returned to the Melbourne Magistrates Court Friday for a largely administrative matter in which March 5 was set for the start of a four-week committal hearing to decide if there is enough evidence from the prosecution for the case to go to trial.

Many of the details cannot be reported for legal reasons. But Magistrate Belinda Wallington said all witnesses would be allowed except five, meaning some 50 could be called up, including former choirboys.

“It is appropriate to allow people's memories to be further explored,” she said.

His barrister Robert Richter suggested it was “impossible” that some alleged incidents occurred at a Melbourne cathedral.

“We propose to demonstrate... that what was alleged was impossible,” he told Wallington.

Pell has not had to enter a plea yet, but at his first appearance at the same court in July he instructed his lawyer to make clear he intended to plead not guilty.

“For the avoidance of doubt and because of the interest, I might indicate that Cardinal Pell pleads not guilty to all charges and will maintain the presumed innocence that he has,” Richter said at the time.

Pell, a former Sydney and Melbourne archbishop, was not required to attend the hearing Friday.

But Australia's most powerful Catholic again opted to appear, having previously vowed to defend himself and clear his name after a two-year investigation led to him being charged on June 29.

Leave of absence

At his first court appearance, he had to battle through a crush of national and international media as he walked the short distance from his barrister's office to the court's main entrance.

Hunched over and looking weary, he again made the same slow trek to and from the court on Friday but with a much heavier police presence and less media, making no comment.

He did not react as several protesters called out abuse on his way in. He was also heckled with screams of “nowhere to hide” as he left.

But he also had supporters, including Carmen Zahra who said: “We know that he is a man of integrity.”

Pell has been granted a leave of absence by the Pope, who has made clear the cardinal would not be forced to resign his post as head of the Vatican's powerful economic ministry.

But the scandal has rocked the church.

Australia's Catholic leaders have previously spoken out in support of him, describing Pell as a “thoroughly decent” man.

Supporters have set up a fund to help him pay his court costs, according to the Institute of Public Affairs, a high-profile conservative Australian think tank.

The allegations coincide with the final stages of Australia's Royal Commission into Institutional Responses to Child Sex Abuse, ordered in 2012 after a decade of pressure to investigate widespread allegations of institutional paedophilia.

The commission has spoken to thousands of survivors and heard claims of child abuse involving churches, orphanages, sporting clubs, youth groups and schools.

Pell appeared before the commission three times, once in person and twice via video-link from Rome.