An Australian court has begun hearing Cardinal George Pell's appeal against his conviction for child sexual abuse.
Pell was found guilty by a jury last year of abusing two boys inside a Melbourne cathedral in 1996. He was later jailed for six years.
The ex-Vatican treasurer, 77, is the most senior Catholic figure to be convicted of such crimes.
He maintains his innocence and argues the verdict was unreasonable.
The hearing, which began on Wednesday, will run over two days in Victoria's Court of Appeal.
Pell was transported from prison to the court in a van, wearing a black suit and his clerical collar.
The Australian cardinal's conviction has rocked the Catholic Church, where he had been among Pope Francis's closest advisers.
What was Pell convicted of?
Last year, the County Court of Victoria heard that Pell had abused two 13-year-old boys following a mass in 1996, when he was archbishop of Melbourne. He abused one of the boys again in 1997, the court was told.
A jury unanimously convicted him on one charge of sexually penetrating a child under 16, and four counts of committing an indecent act on a child under 16.
The trial heard testimony from one of the victims. The other died of a drug overdose in 2014.
Pell chose not to give evidence during the trial.
How is he arguing for an appeal?
Pell is contesting the verdict on three grounds. The first asserts that it was "unreasonable" because it relied too heavily on the testimony of the surviving victim.
The jury had also heard "unchallenged" evidence from 20 other prosecution witnesses, they argue.
The second aspect of the appeal asserts that the trial judge had wrongly prevented a defence animation from being played at the trial.
The video represents the locations of witnesses inside St Patrick's Cathedral. Pell's lawyers argue that he could not have committed abuse because it was impossible for him to be alone.
The third challenge contends that Pell was prevented from entering his plea before a jury - against court process.
What could unfold?
The appeal is being heard by three judges in the Court of Appeal - a division of the Supreme Court of Victoria.
The judges are also simultaneously deciding whether Pell can be granted leave to appeal at all - in other words, whether he is allowed to do so.
A decision requires only two of the three judges to agree.
A successful appeal could result in a retrial or Pell being immediately released, legal experts say.
When could a decision be known?
Experts say it could happen either immediately after the hearings conclude on Thursday, or the judges could reserve their ruling for a later date.
Return to court
Hywel Griffith, BBC News Australia correspondent
After nearly three months as a prison inmate, George Pell has returned to the familiar setting of the courtroom, flanked by a team of security guards.
Once again, the room is packed with both friends and critics of the cardinal, many of whom have sat through every step of this long, winding legal process.
As the lawyers debate the minutiae of his convictions and the concept of reasonable doubt, Pell has been listening intently and taking extensive notes.
The 77-year-old appears to be in good health, no longer depending on a walking stick to move around.
By wearing his clerical collar, he has signalled that he is still a man of the Church who has not been cut adrift by the Vatican.
It will be up to the panel of judges to decide whether the law has dealt with him fairly.
What's been the reaction previously?
Pell's surviving victim - who cannot be named - has previously expressed concern that the verdict could be overturned.
"There is no rest for me. Everything is overshadowed by the forthcoming appeal," he said in March.
The Vatican said they found the conviction to be "painful news", but also that Pell had a right to "defend himself to the last degree".
The cleric was removed from the Pope's inner circle in December, and his term as Vatican treasurer expired earlier this year.