The Censor Librorum is someone who accepts books in the Catholic Church because of the ecclesiastical government and gives the nil obstat, by which imprisonment is granted by or on behalf of the bishop.
The local ordinaris has the right to entrust the judgment about books to people who seem appropriate. In addition, a list of censors available to the diocesan curies can be made by the bishops' conference. It may also set up a committee of censors that may be consulted by the local councilor.
In the performance of his duties, the censor should keep the doctrine of the Church in faith and in sincerity, as instructed by the ecclesiastical disciple and he must give his opinion in writing. If this is favorable, the ordinaris may, in his opinion, grant a discharge (imprimatur), stating his name, date and place of leave. If the Ordinaris does not give it, he must communicate the reasons for the refusal to the writer of the work.
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