Vatican representatives are due to hear evidence today from one of the former altar boys who accused Guam's Archbishop Anthony Apuron of sexual abuse.
Pacific Daily News reports groups of Catholics plan to be there to show support for Roland Sondia and other abuse survivors.
Archbishop Apuron is undergoing a canonical trial sparked by allegations he raped and sexually abused altar boys in the 1970s.
Vatican policy dictates only the Vatican can investigate bishops and archbishops accused of sexual abuse.
At least 17 sexual abuse lawsuits have been filed against Archbishop Apuron, other clergy members and the Archdiocese of Agana.