VATICAN CITY (AP) — The Vatican has sent a Rome-based cardinal who has clashed repeatedly with Pope Francis to the Pacific island of Guam to investigate an important case of sexual abuse.

The Pacific Daily News reports that Cardinal Raymond Burke is scheduled to interview a former altar boy who says he was sexually abused by Guam Archbishop Anthony Apuron.

The 71-year-old Apuron is facing a Vatican trial over multiple allegations of sex abuse of altar boys in the 1970s. He has denied the charges, and has not been criminally charged.

Burke, a doctrinal conservative from the U.S., headed the Vatican's high court until 2014, when Francis removed him and named him patron of the Knights of Malta religious order. Francis recently sidelined Burke from that position after a crisis in the order.