The Vatican is gearing up for a showdown over the global priest sex abuse scandal, forced for the first time to defend itself at length and in public against allegations that it enabled the rape of thousands of children by protecting pedophile priests and its own reputation at the expense of victims.

A United Nations committee on Thursday will grill the Holy See in Geneva on its implementation of the U.N. Convention on the Rights of the Child. Among other things, the treaty calls for signatories to take all appropriate measures to protect children from harm and to put children's interests above all else.

The Holy See, the episcopal jurisdiction of the Roman Catholic Church in Rome, ratified the convention in 1990 and submitted a first implementation report in 1994. But it did not provide progress reports for nearly two decades, and submitted one in 2012 only after coming under criticism following the 2010 explosion of child sex abuse cases in Europe.

Victims’ groups and human rights organizations rallied together to press the U.N. committee to challenge the Holy See on its abuse record, providing written testimony from victims and evidence outlining the global scale of the problem.

Their reports cite case studies in Mexico and Britain, grand jury investigations in the United States and government fact-finding inquiries from Canada to Ireland to Australia that detail how the Vatican's policies, its culture of secrecy and its fear of scandal contributed to the problem.

The submissions reference Vatican documents showing that its officials knew about a notorious Mexican molester decades before taking action. The documents cite correspondence from a Vatican cardinal praising a French bishop's decision to protect his abusive priest, and another Vatican directive to Irish bishops to strike from their policies any mandatory reporting of abusers to police. The submissions even quote the former Vatican No. 2 as saying bishops should not be expected to turn their priests in.

"For too many years, survivors were the only ones speaking out about this and bearing the brunt of a lot of criticism," said Pam Spees, a human rights attorney for the Center for Constitutional Rights, which provided a key report to the committee. "And so this is a very important moment for many, many people who are here in Geneva and around the world who will be watching as the Holy See is called for the first time ever to actually answer questions."

To date the Holy See has never had to defend its record to any large extent or in court, since it has successfully argued that it is immune from lawsuits as a sovereign state and that, regardless, bishops — not the pope or his policies — were responsible for pedophile priests in their care.

While the Holy See has had to answer some questions about abuse at the separate U.N. Human Rights Council, this is the first U.N. hearing dedicated to the issue, and the Vatican was compelled to submit to it as a signatory of the convention. Officials have privately said they are hoping at best to do damage control at Thursday's session.

The Vatican will be represented by its most authoritative official on the issue, Monsignor Charles Scicluna, for a decade the Holy See's chief sex crimes prosecutor. He is credited with having overhauled the Vatican's procedures to better prosecute pedophiles in-house. But the Vatican to date has refused to instruct its bishops to report suspected cases of abuse to police, saying they need do so only when required by local laws.

"When abusers are in jail, they don't harm kids," said Miguel Hurtado, a member of the main U.S.-based victims' advocacy group, Survivors Network of Those Abused by Priests (SNAP), who said he was abused by a priest in the Catholic youth group he attended as a youngster in the Catalonia region of Spain. "And they failed to do that."