Arrest: the power and the necessity test (Code G)

(1) A constable may arrest without a warrant—

(a) anyone who is about to commit an offence;

(b) anyone who is in the act of committing an offence;

(c) anyone whom he has reasonable grounds for suspecting to be about to commit an offence;

(d) anyone whom he has reasonable grounds for suspecting to be committing an offence.

(2) If a constable has reasonable grounds for suspecting that an offence has been committed, he may arrest without a warrant anyone whom he has reasonable grounds to suspect of being guilty of it.

(3) If an offence has been committed, a constable may arrest without a warrant—

(a) anyone who is guilty of the offence;

(b) anyone whom he has reasonable grounds for suspecting to be guilty of it.

(4) But the power of summary arrest conferred by subsection (1), (2) or (3) is exercisable only if the constable has reasonable grounds for believing that for any of the reasons mentioned in subsection (5) it is necessary to arrest the person in question.

(5) The reasons are—

(a) to enable the name of the person in question to be ascertained (in the case where the constable does not know, and cannot readily ascertain, the person's name, or has reasonable grounds for doubting whether a name given by the person as his name is his real name);

(b) correspondingly as regards the person's address;

(c) to prevent the person in question—

(i) causing physical injury to himself or any other person;

(ii) suffering physical injury;

(iii) causing loss of or damage to property;

(iv) committing an offence against public decency (subject to subsection (6)); or

(v) causing an unlawful obstruction of the highway;

(d) to protect a child or other vulnerable person from the person in question;

(e) to allow the prompt and effective investigation of the offence or of the conduct of the person in question;

(f) to prevent any prosecution for the offence from being hindered by the disappearance of the person in question.

(6) Subsection (5)(c)(iv) applies only where members of the public going about their normal business cannot reasonably be expected to avoid the person in question.

2.1 A lawful arrest requires two elements:

A person’s involvement or suspected involvement or attempted involvement in the commission of a criminal offence;

AND

Reasonable grounds for believing that the person’s arrest is necessary.

both elements must be satisfied, and

it can never be necessary to arrest a person unless there are reasonable grounds to suspect them of committing an offence.

2.2 The arrested person must be informed that they have been arrested, even if this fact is obvious, and of the relevant circumstances of the arrest in relation to both the above elements. The custody officer must be informed of these matters on arrival at the police station. See paragraphs 2.9, 3.3 and Note 3 and Code C paragraph 3.4.

2.4 The power of arrest is only exercisable if the constable has reasonable grounds for believing that it is necessary to arrest the person. The statutory criteria for what may constitute necessity are set out in paragraph 2.9 and it remains an operational decision at the discretion of the constable to decide:

which one or more of the necessity criteria (if any) applies to the individual; and

if any of the criteria do apply, whether to arrest, grant street bail after arrest, report for summons or for charging by post, issue a penalty notice or take any other action that is open to the officer.

2.9 When it is practicable to tell a person why their arrest is necessary (as required by paragraphs 2.2, 3.3 and Note 3), the constable should outline the facts, information and other circumstances which provide the grounds for believing that their arrest is necessary and which the officer considers satisfy one or more of the statutory criteria in sub-paragraphs (a) to (f), namely:

(a) to enable the name of the person in question to be ascertained (in the case where the constable does not know, and cannot readily ascertain, the person’s name, or has reasonable grounds for doubting whether a name given by the person as his name is his real name):

An officer might decide that a person’s name cannot be readily ascertained if they fail or refuse to give it when asked, particularly after being warned that failure or refusal is likely to make their arrest necessary (see Note 2D). Grounds to doubt a name given may arise if the person appears reluctant or hesitant when asked to give their name or to verify the name they have given.

Where mobile fingerprinting is available and the suspect’s name cannot be ascertained or is doubted, the officer should consider using the power under section 61(6A) of PACE (see Code D paragraph 4.3(e)) to take and check the fingerprints of a suspect as this may avoid the need to arrest solely to enable their name to be ascertained.

(b) correspondingly as regards the person’s address:

An officer might decide that a person’s address cannot be readily ascertained if they fail or refuse to give it when asked, particularly after being warned that such a failure or refusal is likely to make their arrest necessary. See Note 2D. Grounds to doubt an address given may arise if the person appears reluctant or hesitant when asked to give their address or is unable to provide verifiable details of the locality they claim to live in.

When considering reporting to consider summons or charging by post as alternatives to arrest, an address would be satisfactory if the person will be at it for a sufficiently long period for it to be possible to serve them with the summons or requisition and charge; or, that some other person at that address specified by the person will accept service on their behalf. When considering issuing a penalty notice, the address should be one where the person will be in the event of enforcement action if the person does not pay the penalty or is convicted and fined after a court hearing.

(c) to prevent the person in question:

(i) causing physical injury to himself or any other person;

This might apply where the suspect has already used or threatened violence against others and it is thought likely that they may assault others if they are not arrested. See Note 2D

(ii) suffering physical injury;

This might apply where the suspect’s behaviour and actions are believed likely to provoke, or have provoked, others to want to assault the suspect unless the suspect is arrested for their own protection. See Note 2D

(iii) causing loss or damage to property;

This might apply where the suspect is a known persistent offender with a history of serial offending against property (theft and criminal damage) and it is thought likely that they may continue offending if they are not arrested.

(iv) committing an offence against public decency (only applies where members of the public going about their normal business cannot reasonably be expected to avoid the person in question);

This might apply when an offence against public decency is being committed in a place to which the public have access and is likely to be repeated in that or some other public place at a time when the public are likely to encounter the suspect. See Note 2D

(v) causing an unlawful obstruction of the highway;

This might apply to any offence where its commission causes an unlawful obstruction which it is believed may continue or be repeated if the person is not arrested, particularly if the person has been warned that they are causing an obstruction. See Note 2D

(d) to protect a child or other vulnerable person from the person in question.

This might apply when the health (physical or mental) or welfare of a child or vulnerable person is likely to be harmed or is at risk of being harmed, if the person is not arrested in cases where it is not practicable and appropriate to make alternative arrangements to prevent the suspect from having any harmful or potentially harmful contact with the child or vulnerable person.

(e) to allow the prompt and effective investigation of the offence or of the conduct of the person in question. See Note 2E

This may arise when it is thought likely that unless the person is arrested and then either taken in custody to the police station or granted ‘street bail’ to attend the station later, see Note 2J, further action considered necessary to properly investigate their involvement in the offence would be frustrated, unreasonably delayed or otherwise hindered and therefore be impracticable. Examples of such actions include:

(i) interviewing the suspect on occasions when the person’s voluntary attendance is not considered to be a practicable alternative to arrest, because for example:

it is thought unlikely that the person would attend the police station voluntarily to be interviewed.

it is necessary to interview the suspect about the outcome of other investigative action for which their arrest is necessary, see

(ii) to (v) below.

arrest would enable the special warning to be given in accordance with Code C paragraphs 10.10 and 10.11 when the suspect is found:

in possession of incriminating objects, or at a place where such objects are found;

at or near the scene of the crime at or about the time it was committed.

the person has made false statements and/or presented false evidence;

it is thought likely that the person:

may steal or destroy evidence;

may collude or make contact with, co-suspects or conspirators;

may intimidate or threaten or make contact with, witnesses.

See Notes 2F and 2G

(ii) when considering arrest in connection with the investigation of an indictable offence (see Note 6), there is a need:

to enter and search without a search warrant any premises occupied or controlled by the arrested person or where the person was when arrested or immediately before arrest;

to prevent the arrested person from having contact with others;

to detain the arrested person for more than 24 hours before charge.

(iii) when considering arrest in connection with any recordable offence and it is necessary to secure or preserve evidence of that offence by taking fingerprints, footwear impressions or samples from the suspect for evidential comparison or matching with other material relating to that offence, for example, from the crime scene. See Note 2H

(iv) when considering arrest in connection with any offence and it is necessary to search, examine or photograph the person to obtain evidence. See Note 2H

(v) when considering arrest in connection with an offence to which the statutory Class A drug testing requirements in Code C section 17 apply, to enable testing when it is thought that drug misuse might have caused or contributed to the offence. See Note 2I.

(f) to prevent any prosecution for the offence from being hindered by the disappearance of the person in question.

This may arise when it is thought that:

if the person is not arrested they are unlikely to attend court if they are prosecuted;

the address given is not a satisfactory address for service of a summons or a written charge and requisition to appear at court because the person will not be at it for a sufficiently long period for the summons or charge and requisition to be served and no other person at that specified address will accept service on their behalf.

3.3 A person who is arrested, or further arrested, must be informed at the time if practicable, or if not, as soon as it becomes practicable thereafter, that they are under arrest and of the grounds and reasons for their arrest, see paragraphs 2.2 and Note 3.

(1) Subject to subsection (5) below, where a person is arrested, otherwise than by being informed that he is under arrest, the arrest is not lawful unless the person arrested is informed that he is under arrest as soon as is practicable after his arrest.

(2) Where a person is arrested by a constable, subsection (1) above applies regardless of whether the fact of the arrest is obvious.

(3) Subject to subsection (5) below, no arrest is lawful unless the person arrested is informed of the ground for the arrest at the time of, or as soon as is practicable after, the arrest.

(4) Where a person is arrested by a constable, subsection (3) above applies regardless of whether the ground for the arrest is obvious.

(5) Nothing in this section is to be taken to require a person to be informed—

(a) that he is under arrest; or

(b) of the ground for the arrest,

if it was not reasonably practicable for him to be so informed by reason of his having escaped from arrest before the information could be given.

(1) Subsection (1A) applies where a person is, at any place other than a police station—

(a) arrested by a constable for an offence, or

(b) taken into custody by a constable after being arrested for an offence by a person other than a constable.

(1A) The person must be taken by a constable to a police station as soon as practicable after the arrest.

(1B) Subsection (1A) has effect subject to section 30A (release of a person arrested elsewhere than at police station) and subsection (7)(release without bail).

(2) Subject to subsections (3) and (5) below, the police station to which an arrested person is taken under subsection (1A) above shall be a designated police station.

(3) A constable to whom this subsection applies may take an arrested person to any police station unless it appears to the constable that it may be necessary to keep the arrested person in police detention for more than six hours.

(4) Subsection (3) above applies—

(a) to a constable who is working in a locality covered by a police station which is not a designated police station; and

(b) to a constable belonging to a body of constables maintained by an authority other than a local policing body.

(5) Any constable may take an arrested person to any police station if—

(a) either of the following conditions is satisfied—

(i) the constable has arrested him without the assistance of any other constable and no other constable is available to assist him;

(ii) the constable has taken him into custody from a person other than a constable without the assistance of any other constable and no other constable is available to assist him; and

(b) it appears to the constable that he will be unable to take the arrested person to a designated police station without the arrested person injuring himself, the constable or some other person.

(6) If the first police station to which an arrested person is taken after his arrest is not a designated police station, he shall be taken to a designated police station not more than six hours after his arrival at the first police station unless he is released previously.

(7) A person arrested by a constable at any place other than a police station must be released without bail if the condition in subsection (7A) is satisfied.

(7A) The condition is that, at any time before the person arrested reaches a police station, a constable is satisfied that there are no grounds for keeping him under arrest ....

(8) A constable who releases a person under subsection (7) above shall record the fact that he has done so.

(9) The constable shall made the record as soon as is practicable after the release.

(10) Nothing in subsection (1A) or in section 30A prevents a constable delaying taking a person to a police station or releasing him under section 30A if the condition in subsection (10A) is satisfied.

(10A) The condition is that the presence of the person at a place (other than a police station) is necessary in order to carry out such investigations as it is reasonable to carry out immediately.

(11) Where there is any such delay the reasons for the delay must be recorded when the person first arrives at the police station or (as the case may be) is released under section 30A.

(12) Nothing in subsection (1A) or section 30A above shall be taken to affect—

(a) paragraphs 16(3) or 18(1) of Schedule 2 to the Immigration Act 1971;

(b) section 34(1) of the Criminal Justice Act 1972; ...

(c) any provision of the Terrorism Act 2000 ; or

(d) section 27 of and Schedule 6 to the National Security Act 2023.

(13) Nothing in subsection (1) above shall be taken to affect paragraph 18(3) of Schedule 2 to the Immigration Act 1971.