Pope Benedict XVI has appointed a Boston priest as the Vatican's new sexual crimes prosecutor.

The Vatican said that Rev. Robert W. Oliver, who handled sexual abuse cases in the Roman Catholic Church in Boston at the height of the scandal, would be "the promoter of justice" at the Congregation for the Doctrine of the Faith, the Vatican’s doctrinal office that reviews all abuse cases.

“It is with deep humility and gratitude that I received the news that the Holy Father is entrusting me with this service to the church," said Father Oliver, in a statement released by the Archdiocese of Boston.

Father Oliver will succeed Msgr. Charles Scicluna, 53, who was promoted to auxiliary bishop in Malta in October.

Father Oliver was among the canon lawyers brought in to advise Cardinal Bernard F. Law on sexual abuse cases in Boston in 2002 and was responsible for investigating charges against accused priests when the cardinal was forced to resign after it was revealed that he had kept abusive priests working in parishes.

In 2003, he helped write a new abuse prevention policy for the archdiocese.

However, abuse victim advocates are criticizing Oliver's new appointment.

Anne Barrett Doyle, co-director of a watchdog group called Bishop Accountability, told The New York Times, “Reverend Oliver is a champion of accused priests, which obviously does not bode well for the job he will do as promoter of justice.”

Under his guidance, she said, the Boston archdiocese reported that between 2003 and 2005 it had cleared 32 of 71 accused priests because it did not find “probable cause” to pursue abuse cases against them.

She also said the 2003 abuse policy that Father Oliver helped write  allows accused priests to remain in the ministry without being publicly identified while allegations against them are investigated,yet lay people who work or volunteer for the church are to be suspended immediately if they are suspected of abuse.

Terrence C. Donilon, a secretary for communications for the Archdiocese of Boston, said, “any attacks on Father Oliver’s distinguished track record of service to the church and his many contributions to the response to clergy sexual abuse are unfounded and just plain wrong.”