Pope Francis has taken the biggest step yet to crack down on bishops who cover up for priests who rape and molest children, creating a new tribunal section inside the Vatican to hear cases of bishops accused of failing to protect their flock.

The initiative has significant legal and theological implications, since bishops have long been considered masters of their dioceses and largely unaccountable when they bungle their job, with the Vatican stepping in only in cases of gross negligence.

That reluctance to intervene has prompted years of criticism from abuse victims, advocacy groups and others that the Vatican had failed to punish or forcibly remove bishops who moved predator priests around from parish to parish, where they could rape again, rather than report them to police or remove them from ministry.

The Vatican said Wednesday that Francis had approved proposals made by his sexual abuse advisory board to address that lapse. The board includes two survivors of abuse and experts in child protection policies and their proposals call for a new mechanism by which the Vatican can now receive and examine complaints of "abuse of office" by bishops, and bring them to trial in a Vatican tribunal.

A special new judicial section, with permanent staff, will be created inside the Congregation for the Doctrine of the Faith "to judge bishops with regard to crimes of the abuse of office when connected to the abuse of minors," a Vatican statement said.

Details must still be worked out, including possible punishments and the statute of limitations to determine whether old cases of negligence by bishops dating back 20 or 30 years can now be heard.

The congregation currently reviews all cases of priests who have abused minors and the statute of limitations is 20 years, though the congregation can waive that limit.

"Really pleased the Holy Father has approved our proposal," commission member Marie Collins, herself a survivor of abuse, told The Associated Press in an email.

The main U.S. victims group SNAP was more cautious, noting that there are bishops currently in office who have delayed reporting abuse and yet no punishment has ever been meted out.

"In the face of this widespread denial, timidity and inaction, let's be prudent, stay vigilant and withhold judgment until we see if and how this panel might act," said SNAP's David Clohessy.

The sex abuse scandal exploded decades ago in the U.S., Ireland, Australia, and elsewhere in large part because bishops and heads of religious orders moved pedophile priests around or sent them off for therapy, rather than report the crimes to police and conduct church trials as canon law requires. Their aim was to prevent scandal and hold onto their priests at almost any cost.

In 2001, the Vatican required all bishops and religious superiors to send all their abuse cases to Rome in a bid to crack down on the abusers. In the ensuing years, thousands of priests were sanctioned and hundreds defrocked. But the bosses who enabled them to continue abusing were never punished.

The Vatican had long argued that the pope had little power to sanction bishops when they botched cases of abuse, citing the decentralized structure of the church and the theological concept of a bishop's relationship to Rome. That argument served the Vatican well in the face of U.S. lawsuits seeking to hold the pope ultimately responsible for abusive priests, with the Holy See insisting that the pope doesn't exercise enough control over bishops to be held responsible when they covered up for priests who rape children.

A new tribunal that could enable the pope to essentially fire bishops, and not just passively accept their resignations, would seem to undercut the Vatican's argument of a hands-off pope as far as bishop accountability is concerned.

In April, Francis accepted the resignation of U.S. bishop Robert Finn, who had been convicted in a U.S. court of failing to report a suspected child abuser. It was a sign Francis was cracking down on bishops, but that was a resignation that Finn offered, not a forcible removal.

The Vatican's initiative comes as criminal prosecutors are seeking to hold the church hierarchy responsible for failing to protect children from harm. Recently, prosecutors in Minnesota filed criminal charges against the archdiocese of St. Paul and Minneapolis over its handling of clergy abuse claims, saying church leaders "turned a blind eye" to repeated reports of inappropriate behavior by a priest who was later convicted of molesting two boys.

The archdiocese is facing a fine of a few thousand dollars if convicted. No individuals were named.

The Vatican said Cardinal Sean O'Malley, the head of Francis' sex abuse advisory commission, presented the proposals to Francis' cardinal advisers this week and that they were unanimously approved. Francis also approved them and authorized funding for full-time personnel to staff the new office, the Vatican said.

Francis decided to give the new initiative an initial five years and for the staff of the new office to develop the proposals and evaluate their effectiveness.

Terrence McKiernan, president of the online resource BishopAccountability.org, said the new tribunal was "a promising step" and that it was particularly significant that the Vatican was allocating senior staff and funds to it. But he said there were already several well-known cases of active bishops and cardinals who failed in their duty to protect children.

"This system will be coping with the complex interactions of enabling and offending that we see in cases involving bishops," he said in a statement. "Priests abuse children and so do bishops -- bishops who offend are inevitably enablers, and the commission's plan must confront that sad fact."

Canon law already does provide sanctions for bishops who are negligent in their duties, but the Vatican was never known to have meted out punishment for a bishop who covered up for an abuser.

The Vatican spokesman, the Rev. Federico Lombardi, said that with the new proposals there is now a specific, defined process by which the Vatican can do so.