The mandatory reporting provision marks the first time the Vatican has put into law requirements for Catholic officials to report allegations of sex crimes to police or face fines and possible jail time.
Pope Francis on Friday issued sweeping new sex abuse legislation for Vatican personnel and Holy See diplomats that requires the immediate reporting of abuse allegations to Vatican prosecutors, a policy shift aimed at being a model for the Catholic Church worldwide.
The mandatory reporting provision, while limited in scope, marks the first time the Vatican has put into law requirements for Catholic officials to report allegations of sex crimes to police or face fines and possible jail time.
Francis also issued child protection guidelines for Vatican City State and its youth seminary, acting after the global sex abuse scandal exploded anew last year and The Associated Press reported that the headquarters of the Catholic Church had no policy to protect children from predator priests.
While the new norms only cover Vatican City State, affiliated institutions and the diplomatic corps, they were still symbolically significant and were welcomed by a former seminarian whose case helped spark the reform.
"I see this as something positive," Kamil Jarzembowski, who reported abuse, told the AP.
The law for the first time provides an explicit Vatican definition for "vulnerable people" who are entitled to the same protections as minors under church law.
The Vatican amended its canon law covering sex abuse to include "vulnerable adults" several years ago, but never defined it.
According to the new Vatican definition, a vulnerable person is anyone who is sick or suffering from a physical or psychiatric deficiency, isn't able to exercise personal freedom even on occasion and has a limited capacity to understand or resist the crime.
The issue of whether adult seminarians, religious sisters or other adults who are emotionally or financially dependent on clergy can be considered "vulnerable people" has come to the fore in the wake of the scandal over ex-Cardinal Theodore McCarrick, a once high-ranking American cleric accused of molesting seminarians, and revelations of priests and bishops sexually preying on nuns.
The new law covers all personnel who live and work in the Vatican, the 44 hectare (110 acre) city-state in the centre of Rome, as well as the Holy See's vast diplomatic corps in embassies around the world.
The Vatican's ambassadors have figured in some of the most scandalous cases of sex abuse in recent years, with papal representatives accused of groping, distributing child pornography and sexually abusing minors in their far-flung posts.
The law now requires any Vatican public official who learns of an allegation of abuse to report it to Vatican prosecutors "without delay." Failure to do so can result in a fine of up to 5,000 euros ($5,615) or, in the case of a Vatican gendarme, up to six months of prison.
The legislation requires that victims be welcomed, listened to and provided with medical, psychological and legal assistance, and sets the statute of limitations at 20 years past the victim's 18th birthday.
They must be kept apprised of the investigation.
Victims and their families are to be protected from any retaliation, answering a longstanding problem faced by victims, including Jarzembowski, who reported abuse at the Vatican youth seminary only to be kicked out the following year.
Mimicking some provisions in place in the US church, the provisions require background checks for Vatican staff and volunteers working with minors and calls for safe environment training for all Vatican personnel.
The accused is to be removed from their job pending the investigation, and be allowed to defend themselves.
In a statement accompanying the new law, the Vatican's editorial director, Andrea Tornielli, said while very few children actually live in the Vatican City State, Francis decided to make the legislation and accompanying guidelines a model.
Last year, AP reported that Vatican City had no policy to protect children or require suspected abuse to be reported to police, even though the Holy See required such policies in Catholic dioceses around the globe and had told the UN in 2013 that such a policy was in the works.
The absence of clear-cut policy became evident following revelations that Jarzembowski, then a teenage seminarian in the Vatican's youth seminary had, in 2012, accused one of the older boys of sexually molesting his roommate.
Nothing came of it. Vatican police, who have jurisdiction over the territory, were not called in to investigate. A series of bishops, including Cardinal Angelo Comastri, Francis' vicar for Rome and the archpriest of St. Peter's Basilica, said they investigated, but no one ever interviewed the alleged victim.
Jarzembowski was promptly kicked out of the seminary while the accused seminarian was ordained as a priest.
On Friday, Jarzembowski told AP the law was a positive step forward, particularly its explicit recognition that the pre-seminary falls under its jurisdiction.
"Before there was a situation where a group of kids were there, in the Vatican City State, but they were seemingly in a legal limbo," he said.
He praised the mandatory reporting requirement, noting "the first thing that they [survivor advocacy groups] do is say there must be the obligation to report to public authorities."