Vatican Treasurer Cardinal George Pell was jeered by protesters as he appeared in court on historical sex abuse charges in Australia on Friday.

Australia's most highly-ranked Catholic was not required to enter a plea, but the court heard that about 50 witnesses, including former choir boys, would be called over the length of the trial.

Pope Francis' top financial adviser stands accused of multiple offenses involving multiple complainants, but the exact details of the alleged offenses have been withheld from the public for legal reasons. The court heard that the prosecution's evidence was "voluminous," local media reported.

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Lawyers for the 76-year-old said he would fight the charges, saying at least one of the accusations would have been impossible.

"We propose to demonstrate to Your Honor that what was alleged was impossible," Pell's lawyer Robert Richter told magistrate Belinda Wallington in the Melbourne Magistrates Court.

Richter noted that one witness had only given police a "vague" statement. Judge Wallington responded that the man was aged 11 at the time.

"We're dealing with historical events. Memory's not static," the judge said. Wallington approved the defense's cross examination of many but not all witnesses.

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Special privileges are gone

Outside the court, protester Helen Dawson told Melbourne's Herald-Sun newspaper that although brief, today's court appearance by Pell was very significant.

"This trial is a very important display that the days of special privileges for high-ranking religious officials are finished and gone," she said.

Pell will face court again next month and then next year for a committal hearing to determine whether it should proceed to a full trial.

Pope Francis, who pledged a "zero tolerance" policy on sex abuse in the church, granted Pell a leave of absence from his Vatican role to defend the charges. The pontiff said he would not comment on the case until it is over.

aw/rt (AP, AFP, Reuters, dpa)