Generally, trespass is a civil law offence, which means that the police have no power to arrest you for it.
Trespass is entering – or putting property on – land that belongs to someone else, without their permission.
If you have ‘implied permission’ to enter somewhere – for instance a shop open to members of the public – then you are not committing trespass until you have been asked to leave by the owner of the building or their representative. In a shop this is often a manager, but should not be police officer. If you fail to do so, then you could be taken to a civil court (‘sued’) by the owner.
When protesters occupy a building or land, landowners can lawfully use reasonable force to remove trespassers in an emergency but risk committing an assault or breaching Section 6 of the Criminal Law Act 1977, which makes it an offence to use violence to secure entry onto ‘premises’ (which includes buildings, land around it or a site with a number of buildings).
Section 6 explicitly says that “the fact that a person has any interest in or right to possession or occupation of any premises shall not… constitute lawful authority for the use or threat of violence.”
Landowners, leaseholders or holders of a licence to use land or property are more likely to therefore apply to the civil courts for a ‘possession order’, which requires that the claimant is granted possession (exclusive physical control).
Protesters may also face the threat of an ‘injunction’ – a court order that instructs them to stop an existing activity or refrain from undertaking a particular future action. For more information, see our guide to dealing with injunctions.