Josef Wesolowski Vatican Child Abuse
Archbishop Josef Wesolowski was found guilty of sex abuses by a Vatican court.Reuters

The former Holy See envoy to the Dominican Republic has been convicted and defrocked over child abuse in an unprecedented trial at the Vatican.

The Congregation for the Doctrine of the Faith, the Vatican office tasked with overseeing the Church's integrity, also known as the Holy Office, found Polish archbishop Josef Wesolowski guilty of sex abuse during his tenure as papal nuncio in Santo Domingo.

The canonical trial's verdict conferred a sentence of laicization - the banishment of a priest from the clergy. It is the harshest penalty possible the Holy Office can hand to a cleric.

The 66-year-old is also facing the prospect of imprisonment in the Vatican's tiny jail, as, when all appeals are exhausted, he will be tried by a criminal tribunal of the city state.

Wesolowski has two months to appeal. During that time, the Vatican said that he will be placed under some unspecified restrictive measures.

The Polish clergyman served as the Apostolic nuncio to the Dominican Republic from 2008 to August 2013, when he was recalled to the Holy See after the archbishop of Santo Domingo, Cardinal Nicolas de Jesus Lopez, told Pope Francis about claims that Wesolowski had sexually abused teenage boys.

Wesolowski had been exposed by a local television station, which alleged he hired "rent boys".

A 13-year-old boy working as a shoeshiner told NCDN channel that the archbishop paid him to masturbate in his presence and filmed the act on his mobile phone.

The case caused great embarrassment to the Vatican as Wesolowski was an official representative of the Pontiff and had been ordained as a priest and bishop by Pope John Paul II, who has recently been made a saint.

Wesolowski is the highest-ranking Vatican official ever to be investigated for sex abuse, and has become the first top papal representative to receive a defrocking sentence.