Films that are banned in Australia have been considered to be offensive against the standards of morality, decency and propriety generally accepted by "reasonable adults" to the extent that they should not be classified.
Films can be banned by the Australian Classification Board if they "depict, express or otherwise deal with matters of sex, drug misuse or addiction, crime, cruelty, violence or revolting or abhorrent phenomena in such a way that they offend against the standards of morality, decency and propriety generally accepted by reasonable adults to the extent that they should not be classified", "describe or depict in a way that is likely to cause offence to a reasonable adult, a person who is, or appears to be, a child under 18 (whether the person is engaged in sexual activity or not)", or "promote, incite or instruct in matters of crime or violence".
Additionally, the RC classification is mandatory for any classifiable work that advocates the commission of a terrorist act under section 9A of the Classification Act of 1995.
Films that are banned by the Australian Classification Board are labelled "Refused Classification" (RC), and the sale, distribution, public exhibition and/or importation of RC material is a criminal offense punishable by a fine up to A$687,500 and/or up to 10 years imprisonment.
With this in mind, it is legal to access films that are RC material via the internet, while personal ownership of films that are RC material is legal except in Western Australia and prescribed areas of the Northern Territory and/or if the films contain illegal content (i.e. child abuse material).