The Catholic Archbishop of Adelaide, Philip Wilson, has been charged over the alleged cover-up of child sex abuse by the Catholic Church in the Maitland-Newcastle region.

The charge relates to the 64-year-old's alleged failure to report child sex abuse carried out by priest James Fletcher during the 1970s.

Charged: Archbishop Philip Wilson. Credit:David Mariuz

Fletcher died in 2006, a year after he was jailed for at least seven and a half years following his conviction of nine sexual abuse charges relating to a teenager between 1989 and 1991.

A special commissioner of inquiry into the alleged cover-up of child sexual abuse by the church in the Hunter region found that Fletcher had an "extensive history of sexually abusing children in the Diocese, exclusively abusing young males and particularly altar boys.

"His offending history dates back at least to the 1970s," the inquiry found.

Archbishop Wilson is due to appear in Newcastle Local Court on April 30.