Apostolic Administrator

An apostolic administrator in the Roman Catholic Church is a prelate appointed by the Pope to serve as the ordinary for an apostolic administration. An apostolic administration can either be an area that is not yet a diocese (a stable 'pre-diocesan', usually missionary apostolic administration) or for a diocese, eparchy or similar permanent ordinariate (such a territorial prelature or a territorial abbacy) that either has no bishop (an apostolic administrator sede vacante, as after an episcopal death or resignation) or, in very rare cases, has an incapacitated bishop (apostolic administrator sede plena).

Apostolic administrators of stable administrations are equivalent in canon law with diocesan bishops, meaning they have essentially the same authority as a diocesan bishop. This type of apostolic administrator is usually the bishop of a titular see.

Administrators sede vacante or sede plena only serve in their role until a newly chosen diocesan bishop takes possession of the diocese. They are restricted by canon law in what they can do to the diocese they temporarily administer. For example, such an administrator may not sell real estate owned by the diocese. This type of administrator is commonly an auxiliary bishop of the diocese, a priest serving as the vicar general of the diocese, or the ordinary of a neighboring diocese.

Normally when a diocese falls vacant, either the previously appointed Coadjutor bishop takes possession of the see or (lacking such successor) a vicar capitular/diocesan administrator is chosen locally, but the Pope, having full governmental power, can preempt this choice and name an apostolic administrator instead. Sometimes a retiring, promoted or transferred (arch)bishop is designated to be apostolic administrator until his successor is designated and takes office, sometimes the Metropolitan or a fellow suffragan is appointed.

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