VATICAN CITY (Reuters) - Cardinal George Pell has become the highest ranking Roman Catholic prelate to be convicted on charges of sexual abuse.

FILE PHOTO: Pope Francis signs a cricket bat of Canterbury cricket team received from Cardinal George Pell at the Vatican, October 29, 2015. REUTERS/Osservatore Romano/Handout via Reuters/File photo

The ruling has shaken the Church from remote corners of his native Australia to the frescoed halls of the Vatican, and could lead to a tug-of-war between Church justice and civil justice.

Pell, 77, was remanded in custody pending sentencing for sexually abusing two choir boys in Australia two decades ago.. He had pleaded not guilty to the charges.

The imprisonment of someone Pope Francis had chosen as a top advisor in the Vatican -- unthinkable to many just a few months ago -- has put the pope in a difficult position.

Francis is under pressure from victims of sexual abuse and their advocates to remove Pell from the position of cardinal for the good of the Church or dismiss him from the priesthood.

But Pell, who gave up Vatican immunity to return home to defend himself, is appealing the verdict. The pope has said he will wait for Australian civil justice to take its course before commenting on the case publicly.

WHAT IS PELL’S POSITION IN THE CHURCH?

Pell is still a member of the College of Cardinals, the elite group from around the world who head dioceses and advise the pope. Cardinals under 80 can enter a secret conclave to elect a new pontiff after a papal death or resignation.

Pell could, in theory, offer his resignation as a cardinal while still proclaiming his innocence ahead of an appeal if he felt that relinquishing that rank and title could help ease the embarrassment to the Church of having a cardinal in jail.

But those who know Pell and his combative nature say this is highly unlikely.

Only the pope could accept Pell’s resignation from the College of Cardinals.

WHAT HAPPENS IF PELL RESIGNS AS A CARDINAL?

Even if Pell resigns as a cardinal, he would keep the title of archbishop, but it would largely be an honorific one because he no longer heads a diocese.

More importantly, he would still be a priest.

Before Pell could be dismissed from the priesthood, the Vatican’s Congregation for the Doctrine of the Faith (CDF) would have to find him guilty following a separate canonical trial or abbreviated procedure, known as an “administrative process”.

The Vatican said on Wednesday the CDF was looking into the accusations against Pell.

The CDF could use information from the trial in Australia. But that information would have be entered formally into the Vatican’s canonical judicial procedures -- as would happen if imported into any other country or institution’s judicial system.

Depending on developments in the next few weeks and months, Pell could find himself in the awkward position of being seen as innocent by his Church but guilty by his government.

ARE THERE PRECEDENTS FOR THE RESIGNATION OF A CARDINAL?

Last year, the pope accepted the resignation as cardinal of Theodore McCarrick, the former archbishop of Washington, D.C., after accusations that McCarrick had sexually abused a minor more than 50 years ago. Last month, after a CDF “administrative process” found him guilty of sex crimes against minors and adults, the pope dismissed McCarrick from the priesthood.

But, unlike Pell, McCarrick had not faced any civil procedures in his home country, the United States. He was tried and found guilty in the Vatican according to canon (Church) law.

McCarrick has responded publicly to only one of the allegations, saying he has “absolutely no recollection” of an alleged case of sexual abuse of a 16-year-old boy more than 50 years ago.

WHAT IS PELL’S CURRENT POSITION IN THE VATICAN?

Pell no longer has any position in the Vatican. In 2014, Pope Francis made him Prefect of the Secretariat of the Economy, a new office to oversee the Vatican’s finances and introduce uniform accounting standards in its departments.

In June, 2017, when Pell returned to Australia to defend himself, he took a leave of absence from the post. His five-year mandate expired on Feb. 24. Two days later, the day his conviction in Australia was made public, the Vatican announced that he was no longer the head of the department even though a successor had not been named.

WHAT IS PELL’S LEGAL POSITION IN AUSTRALIA

Pell is in the maximum security Melbourne Assessment Prison awaiting a sentencing hearing scheduled for March 13. Each of the five offences of which Pell was found guilty carries a maximum 10 years imprisonment.

His lawyers have announced an appeal. A judge will first need to weigh the grounds for the appeal and then decide whether it can proceed. There is no date set for this yet.

If that judge allows it, an appeals hearing proceeds. If the judge refuses, Pell can also appeal against that refusal.

If the appeal goes ahead, a judge could allow the conviction to stand, acquit Pell or order a re-trial.

The process is likely to take months.

HAVE OTHER ROMAN CATHOLIC CARDINALS BEEN JAILED BEFORE?

Pell is the first cardinal in living memory to be jailed following a trial of due process in a Western country.

During the Cold War, Cardinal Jozsef Mindszenty of Hungary was jailed by the communist leadership. He was arrested in 1948 and accused of treason and conspiracy and later underwent a show trial. He was freed from prison during the Hungarian uprising of 1956 against Soviet rule. When Moscow crushed the uprising, Mindszenty took refuge in the U.S. embassy, where he lived for 15 years.

HOW HAS THIS AFFECTED CHURCH “POLITICS”?

Pell is a prominent figure on the Catholic Church’s conservative wing, a stickler for liturgical detail and doctrinal tradition. His conviction underscored the existing polarization.

Conservative Catholic media and commentators rushed to his defense.

“There are many holes in the story that led to Pell’s conviction,” wrote William Donahue of the U.S.-based Catholic League, adding that Catholics should pray for Pell because the “hysteria and the animus that exist makes for a toxic environment”.

American author, theologian, and religious affairs commentator George Weigel, writing in the conservative religion journal First Things, called the verdict “perverse”. The headline of the column was: “The Pell Affair: Australia is Now on Trial”.

But Anne Barrett Doyle, co-director of BishopAccountability.org, a U.S.-based group which tracks clergy abuse, said in a statement: “The Australian judicial system today put the Catholic Church on equal footing with other institutions.”