Four members of Pope Francis' sex abuse advisory commission are heading to Rome to voice their concerns in person about Francis' appointment of a Chilean bishop accused of covering up for a notorious molester.

Commission member Marie Collins said she and three other commission members will meet later Sunday with Francis' point-man on abuse, Cardinal Sean O'Malley of Boston, to relay their concerns about the appointment of Juan Barros as bishop of the diocese of Osorno.

Victims of Chile's most notorious abuser, the Rev. Fernando Karadima, say Barros knew of and even witnessed Karadima's abuse decades ago.

Collins says if Barros doesn't appreciate that Karadima's behavior then was inappropriate, "then he doesn't understand child abuse" and shouldn't be in charge of a diocese and responsible for protecting children from pedophiles.