1970

It was recognized that teenagers had specific concerns of their own which ought to be reflected in the category system.

1970
Introduction of the 'AA' was finally approved by local authorities and the industry. The minimum age for 'X' certificate films was raised from 16 to 18. The 'A' category was split to create 'A' (which permitted admissions of children aged 5 or over whether accompanied or not but warned parents that the film may contain unsuitable material) and 'AA' (allowed admission of those over 14, but not under 14, whether accompanied or not.

1971
Stephen Murphy became Secretary of the Board.

1973
The Exorcist was accused of having psychologically damaging effects on young people and classified with an 'X' but the decision of the BBFC was overturned by a number of local authorities.

1975
James Ferman became Secretary of the Board and the first film that he looked at was The Texas Chain Saw Massacre which his predecessor had already refused to classify shortly before his departure. Ferman agreed that the violence and terrorisation in the film was unacceptable.

During his time, Ferman permitted increasingly explicit sexual material whilst clamping down on sadistic violence and sexual violence. His attitudes and policies reflected a more general shift of public concern during the 70s.

1977
The extension to the Obscene Publications Act gave the BBFC more latitude when considering depictions of sex in films since they now had to be considered 'as a whole'