The Legion of Decency

The Legion, whoever they were, rated movies according to what Catholics should or should not watch and posted their list of current movies and their ratings in the back of the churches. It was sort of like G and PG and NR and X only they used A, B and C. C meant the movie was completely objectionable and, I suppose, watching a C movie was a sin. Brigitte Bardot was regularly listed in the C section. OK, fair enough. But why was Androcles and the Lion given a C rating?