A law introduced a decade ago to protect women from stalkers is being used by BAA to attempt to curb protest action at Heathrow.

The authority is not the first organisation to turn to the Protection from Harassment Act to seek to restrict protests. However, the Act has been used mainly to curb demonstrations and other action by animal rights activists rather than against environ-mental campaigners.

Several firms targeted by animal rights groups have won “exclusion zones” around premises and employees’ homes. But Oxford University lost in an attempt to curb protests in a wide area of the city when a judge called the zone “inordinately large” and “impossible to identify”.

Under the Act the courts are able to bar individuals from gathering in specific areas or from targeting individuals. Anyone breaching the order is guilty of a criminal offence.

The Act created four new offences: harassment, which carried a maximum of six months in jail; putting someone in fear of violence, which carries a maximum term of five years; breaching a civil injunction barring an individual from a particular area, which carries a maximum five years in jail; and breach of a restraining order, carrying the same penalty.

BAA’s injunction named four individuals and the organisations to which they belonged, including one supported by a range of groups.

Lawyers said that the injunction – if it did seek to ban members and supporters from setting foot near Heathrow and transport links to the airport, including the Heathrow Express rail link from Paddington, the Piccadilly line and sections of the M4 and M25 – would be impossible to police.

Liberty, the civil rights group, called it an example of a “dangerous and undemocratic trend” by large companies to seek to limit the right to protest.

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