The Broadcasting Act 1981 (c. 68) is an Act of the Parliament of the United Kingdom. The effect of the Act was to consolidate the previous Independent Broadcasting Acts 1973, 1974 and 1978 and the Broadcasting Act 1980. The Act was repealed by the Broadcasting Act 1990. It was under this Act (and the BBC Licence and Agreement) that the Sinn Féin broadcast ban from 1988 to 1994 was originally implemented.
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Broadcasting Act 1981 Wikipedia(Text) CC BY-SA