The Australian Classification Board was formed in 1970.
Failure to obtain classification is an implicit ban (except for exempt films and games, and publications whose content is not sufficient to warrant restriction to adults) and the Classification Board occasionally refuses to give classification.
All feature films, videos, computer games, and magazines that contain sexual content for commercial release are required to be submitted to this body, made up of "community representatives" appointed by the government for three- or four-year terms.
According to the broadcast services act 1992 the board is not responsible for classifying material on broadcast media; this is completed by the Australian Communications and Media Authority (ACMA).
Since the federal Parliament has no power to criminalise the domestic sale or exhibition of printed matter within the States or Territories of Australia, as part of the scheme, the States and Territories pass their own laws criminalising such sale and exhibition.
If the Classification Board believes an unclassified work, in their estimation would receive an X18 classification if it were to be classified they will not grant an exemption for public screening as an X18 cannot be exhibited.