One of the categories of arrest that seems most likely to trigger a subsequent claim for damages is that following entry into domestic premises without a warrant. Claims for trespass, assault and false imprisonment are costly for the force, in terms of legal fees, time and resources, officer morale and reputation.

Claimants may feel particularly aggrieved: their privacy has been violated, and they will seize the moral high ground: an Englishman’s home continues to be seen as their castle. The courts are receptive to concerns about trespass and invasion of privacy. This was the case for centuries before the right to privacy and family life was enshrined in the Human Rights Act 1988 (Schedule 1, Article 8).

Over the years, judges have given firm guidance to constables, imposing a high legal threshold, for crossing the threshold into a person’s home. Nevertheless, the frequency with which civil claims are brought, and need to be settled, suggests that some confusion lingers. This may be because some of the case law is counter-intuitive; or perhaps the guidance is simply not being heeded, for instance because of poor training.