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

The initiative, announced Wednesday, 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 from parish to parish, where they could rape again, rather than report them to police or remove them from ministry.

The Vatican said Francis had approved proposals made by his sexual abuse advisory board, which includes survivors of abuse as well as experts in child protection policies. The proposals call for a new mechanism by which the Vatican can 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 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.

”I sincerely believe this is a real step forward,” commission member Marie Collins, a survivor of abuse, said in an email. ”Time will tell the effectiveness of the new measure, but I am hopeful.”

The main U.S. victims group SNAP was more cautious, noting that bishops currently in office 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 or conduct church trials as canon law requires.

In 2001, the Vatican required all bishops and religious superiors to send abuse cases to Rome in a bid to crack down on the abusers. Thousands of priests were sanctioned and hundreds defrocked, but the bosses who enabled them to continue 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.