In the European Directive, "Television Without Frontiers" or TVWF, Article 22 permits the Secretary of State for Culture, Media and Sport to take action against foreign satellite channels that repeatedly broadcast material that "might seriously impair the physical, mental or moral development of minors".
This particularly applies to programmes that involve pornography or gratuitous violence. The 1990 and 1996 Broadcasting Acts gives the Secretary of State power to proscribe such a channel. Before the Secretary of State can proscribe a channel, Ofcom must inform us that the channel is broadcasting unacceptable material.
A proscribed channel cannot be lawfully marketed in the UK. It also becomes an offence to supply (or offer to supply) decoding equipment primarily for the purpose of receiving a proscribed service within the UK. This does not necessarily stop the channel from broadcasting - only action by the licensing Member State can do that, if they agree with the UK.