A U.S.-based group that tracks how the Catholic hierarchy deals with allegations of sexual abuse by clergy says Pope Francis made a “troubling” choice in appointing an Argentine prelate to a powerful Vatican office that handles such cases.

On Saturday, the Vatican announced the pontiff had picked Monsignor Victor Manuel Fernández, archbishop of La Plata, Argentina, to head the Holy See’s watchdog office for doctrinal orthodoxy. Its mandate includes handling sex abuse allegations lodged against clergy.

BishopAccountability.org, a 20-year-old Massachusetts organization that maintains an online archive of abuse in the Roman Catholic Church, said in a statement that the prelate in 2019 refused to believe victims who accused a priest in the La Plata archdiocese of sexually abusing boys.

Francis “made a baffling and troubling choice,’’ the group said in statement emailed late Saturday in the U.S., citing how Fernández handled the case.

“In his response to allegations,…