False arrest, unlawful arrest or wrongful arrest is a common law tort, where a plaintiff alleges they were held in custody without probable cause, or without an order issued by a court of competent jurisdiction. Although it is possible to sue law enforcement officials for false arrest, the usual defendants in such cases are private security firms.
United Kingdom
In the United Kingdom, a police officer may arrest a person if they are executing a warrant, if they have a "reasonable belief" that someone is involved in a criminal offence, or if they have a reasonable belief that someone is about to be involved in a criminal offence and it is necessary to arrest that person. Proof of wrongful arrest depends on proving that an officer did not have a reasonable belief and that it was not necessary to arrest someone.
Most cases where unlawful arrest was determined emerge from a claim that an arrest was unnecessary.
The specific legislation governing, in England and Wales, the reasons for which a police officer may arrest a person are in section 24 of the Police and Criminal Evidence Act 1984.
Damages for unlawful arrest depend primarily on the time in custody and can be aggravated if the police acted maliciously.
United States
After an arrest, if the charges are dropped, a person will sometimes file legal action or a complaint against the appropriate arresting agency. In most jurisdictions, the arrest powers of police and police agents are in excess of those afforded to ordinary citizens (see citizen's arrest). However, the powers of police officers to arrest are not unlimited. Generally speaking:
Anyone may arrest a person if in possession of an arrest warrant issued by an appropriate court. In the United States, this includes bounty hunters (agents of bail bondsmen) acting under the authority of a bench warrant to bring a criminal defendant who has skipped bail to court for trial. A police officer, or a person authorized by a jurisdiction's police powers act, may arrest anyone whom the officer has probable cause to believe has committed any criminal offence. However, in the case of a misdemeanour, summary conviction offence, or non-criminal offence (such as a municipal by-law offence) the officer may arrest the suspect only long enough to identify the suspect and give the suspect a summons to appear in court, unless there is reason to believe they will not appear in answer to the summons. Any person may arrest someone suspected of committing a felony or indictable offence, as long as the arresting person believes the suspect is attempting to flee the scene of the felony scene. A person cannot be arrested on suspicion of committing a felony well after the fact unless the arresting officer possesses an arrest warrant.
Citizens and businesses
Most cases of false arrest involve accusations of shoplifting, and are brought against security guards and retail stores. A guard cannot arrest someone merely on the suspicion that person is going to commit a theft. In most jurisdictions, there must be some proof that a criminal act has actually been committed. For example, a guard does not have reasonable and probable cause if a shopper has not yet paid for merchandise they are carrying in the belief that the person intends to leave without making payment. Instead, there must be an actual act committedthe person must make an actual attempt to leave the store without paying for the merchandise.
Police officers
In the United States and other jurisdictions, police officers and other government officials are liable for clear deprivation of rights, but are partially shielded from false arrest lawsuits through the doctrine of qualified immunity, when such a violation qualifies as "not obvious," by a US Supreme Court test. This doctrine can protect officials from liability when engaged in legal grey areas including qualifying discretionary actions in the arrests of suspects. However, the officer's actions must still not violate "clearly established law," or this protection is void. This includes executing an arrest warrant against the wrong person. False statements by public servants to justify or cover up an illegal arrest are another violation of federal law.