Father Oliver was among the canon lawyers brought in to advise Cardinal Bernard F. Law on sexual abuse cases in Boston, where the church’s abuse scandal erupted anew in 2002. He was put in charge of the office investigating charges against accused priests after the cardinal was forced to resign in 2002 amid an uproar over revelations that he had kept abusive priests working in parishes.

Father Oliver helped write the archdiocese’s new abuse prevention policy in 2003. He has been serving as the top canon lawyer for the archdiocese and as a visiting professor of canon law at Catholic University of America in Washington.

Advocates for abuse victims in the Boston archdiocese criticized his record on Saturday. Anne Barrett Doyle, co-director of Bishop Accountability, a watchdog group that maintains an archive of abuse cases and documents, said in an interview, “Reverend Oliver is a champion of accused priests, which obviously does not bode well for the job he will do as promoter of justice.”

She said that under that under Father Oliver’s guidance, the Boston archdiocese reported that between 2003 and 2005 it had cleared 32 of 71 accused priests, about 45 percent, saying it did not find “probable cause” to pursue abuse cases against them. That was a far higher clearance rate than the 10 percent reported by other dioceses nationwide, according to a report in 2005 by the United States Conference of Catholic Bishops.

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