In the Roman Catholic Church, the Censor Librorum is an ecclesiastical authority charged with reviewing texts and granting the nihil obstat. The Latin Censor Librorum translates as "censor of books."
While the title may suggest the function of suppressing books critical or otherwise unpopular with the Church, this is not the function of the Censor Librorum. Rather, it is the responsibility of the Censor Librorum to review texts for doctrinal accuracy. A text that is doctrinally correct (that is, does not contain any statements that contradict Church doctrine) but portrays the Church or Church officials in a negative manner must still be granted the nihil obstat.
The office of Censor Librorum is a diocesan office, appointed by the diocesan bishop. The function is typically performed by a priest, but if no priest is available, the function could be performed by a theologically educated layperson under a special dispensation.
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