Parker v The Chief Constable of Essex Police

For an unlawful arrest, a defendant seeking to limit damages to nominal damages must prove that the claimant would, not merely could, have been lawfully arrested in the counterfactual. Lawfulness under Police and Criminal Evidence Act 1984, section 24 requires the arresting officer personally to hold the relevant suspicion and belief on reasonable grounds. The statutory necessity requirement is distinct from a Wednesbury challenge and requires reasonable grounds for believing that arrest is necessary. The threshold for reasonable suspicion is low, but the police must assess the quality and reliability of the information available in the circumstances. The counterfactual is fact-sensitive and must reflect what would probably have happened if the tort had not occurred.

The claimant, Michael Ciaran Parker, brought proceedings against the Chief Constable of Essex Police alleging unlawful arrest and false imprisonment. Liability had already been determined in his favour because the officer who arrested him lacked the information required by O’Hara v Chief Constable of RUC. The defendant accepted liability but contended that the claimant was entitled only to nominal damages because he would otherwise have been lawfully arrested by the designated officer.

The preliminary issue was whether the claimant could and would have been lawfully arrested but for the unlawful arrest, applying the principles in R (Lumba) v Secretary of State for the Home Department. The court considered the requirements of suspicion and necessity under section 24 of PACE and the appropriate counterfactual.

1. Lawful arrest. The arresting officer must personally suspect that an offence has been committed, suspect that the person arrested is guilty, believe that arrest is necessary for a reason in section 24(5), and hold each state of mind on objectively reasonable grounds. The court formulated the adjusted Castorina v Chief Constable of Surrey questions to reflect the statutory necessity requirement.
2. Information and reasonable suspicion. An officer may rely on information supplied by others, including hearsay and intelligence, but may not simply obey an order. The relevant material is that in the arresting officer’s mind. The court must assess its quality, reliability and context. Further inquiry may be required where the circumstances make reliance without inquiry unreasonable. The threshold for reasonable suspicion is low and falls well short of a prima facie case.
3. Application. The designated arresting officer, DC Jenkins, could have arrested the claimant lawfully. There were reasonable grounds to suspect that rape and murder had been committed and that the claimant, one of a small closed group with the opportunity to commit the offences, was guilty. The serious medical evidence and operational need for simultaneous arrests supplied reasonable grounds for believing arrest was necessary. The unreliable bad-character material and weak medical-centre information could not properly be relied upon, but their removal did not eliminate reasonable suspicion.
4. Counterfactual and damages. Under R (Lumba) v Secretary of State for the Home Department, the defendant had to prove that lawful arrest would have occurred, not merely that it could have occurred. The proper counterfactual was what would probably have happened if the unlawful arrest had not taken place, without assuming that the officers would appreciate the legal defect or wait for the designated officer. The evidence showed that another surveillance officer would have arrested the claimant on sight and would also have done so unlawfully.
5. Disposition. The defendant failed to establish that the claimant would have been lawfully arrested. The claimant was therefore not restricted to nominal damages.