1. Arrest and Detention

Arrest and Detention Summary #

General points: #

Section 9 of the Charter guarantees everyone a right “not to be arbitrarily detained or imprisoned.”

A detention will be arbitrary under s. 9 if it is not authorized by law, the law under which it is authorized is itself arbitrary, or the detention is not carried out in a reasonable manner (Le).

Police may question, but if not detained or under arrest, a person may refuse to cooperate (including ID, unless there is a legal requirement to provide this). (Grant, Le)

Police have the power to carry out an ‘investigative detention’ where they have a reasonable suspicion implicating the person in an offence being investigated and where it is reasonably necessary on an objective view of the totality of the circumstances (Mann). An investigative detention triggers 10(a) and (b) of the Charter [more detail below].

Police also have the power to carry out a limited frisk search incident to investigative detention where they have a reasonable suspicion that safety is at risk.

Police may arrest on grounds set out in section 495(1) and in certain other situations (under statute and common law: e.g., breach of the peace under s. 31 of the Code and at CL: Hayes v Thompson).

Police may carry out a limited search incident to arrest without requiring further grounds. A strip search upon arrest requires additional grounds, and a strip search at the scene of arrest requires grounds in addition to those [more detail below].

Arrest powers under the Criminal Code: #

Pursuant to section 495(1) of the Criminal Code, a PO may arrest a person where the officer has reasonable grounds to believe that an individual is subject to an arrest warrant, or has committed or is about to commit an indictable offence [which includes a hybrid offence], or if she finds a person committing any offence. 1

The Supreme Court in Storrey held that a valid arrest under s. 495(1)(a) requires that the officer to hold the ‘reasonable belief’ subjectively and that the belief be objectively reasonable, which is to say “a reasonable person, standing in the shoes of the police officer, would have believed that reasonable and probable grounds existed”.

Persons other than peace officers may arrest without a warrant anyone they find committing an indictable office, or anyone they have reasonable grounds to believe has committed a ‘criminal offence’ (summary or indictable) and is being freshly pursued by someone with lawful authority to arrest: s. 494.2

A PO or civilian may use as much force as is reasonably necessary to effect a lawful arrest, s. 25(1).

For a range of offences set out in section 495(2) [summary, hybrid, and offences under s. 553], police must release a person immediately after “arrest” (or in lieu of carrying out a full arrest) unless detaining them further is necessary for any of the “public interest” reasons set out in s. 495(2) (ID, evidence, avoiding continuation/repetition of offence, or to ensure court attendance).

Under section 529.3(1) of the Criminal Code, police may enter a dwelling house without a warrant in order to carry out an arrest where they have reasonable grounds to believe the person is present and the conditions are present to obtain a warrant under 529.1 (RPG) but due to exigent circumstances this is not practicable. For the purposes of this section, exigent circs are defined 529.3(2) to require (a) reasonable grounds to suspect that it is necessary to prevent imminent danger of bodily harm or death, or (b) reasonable grounds to believe that entry is necessary to prevent against the imminent loss or destruction of evidence of an indictable offence.

Ancillary Powers (Common Law): #

1. Search Incident to Arrest #

Police are authorized at common law to conduct a search incident to arrest where:

  1. the arrest is lawful;
  2. the search is truly incidental to the arrest (i.e., conducted for a valid law enforcement purpose related to the reason for the arrest); and
  3. the search is conducted reasonably.

(Fearon)

No additional grounds

At common law, when police carry out a lawful arrest, they also have authority to carry out a limited search incident to arrest without needing separate and additional grounds.

Scope of SITA

SITA may entail a brief pat down of clothing (but not the removal of clothing) and the search of pockets, bags, and “immediate surroundings” (Cloutier). The latter can include the inside of a car in which (or close to which) a person is arrested (Caslake).

Valid criminal justice objective

The Court in Cloutier and Caslake held that a search incident to arrest must be carried out for a “valid objective in pursuit of the ends of criminal justice”, such as:

  1. the discovery of an object that may be a threat to the safety of the police, the accused or the public, or that may facilitate escape;
  2. the discovery evidence against the accused;
  3. the preservation of evidence from destruction.

A search incident to arrest may not be conducted to intimidate or be carried out in an abusive manner. (Cloutier)

Time and distance

Search of things seized upon arrest may also be carried out later in time, or at a distance from the place of the arrest, if the search is carried out for a valid criminal justice purpose connected to the offence for which the person was arrested and there is a reasonable explanation for the delay. (Caslake)

Truly incidental

Where there is an issue as to whether a search was truly incidental to arrest (whether it was conducted for a criminal justice objective connected to the offence for which the person was arrested), the court will apply a twofold test:

(a) did the officer subjectively conduct the search for a an objective connected to the reason for the arrest; and

(b) was this objectively reasonable in the circumstances? (Caslake)

For example, in Caslake, the car was searched not to advance a legitimate criminal justice objective, but merely as part of a police policy to ensure the safekeeping of goods seized. The officer thus lacked a subjective intent tied to the reason for the arrest. But if he did act with this intention, it would have been objectively reasonable, given the clear connection between the reason for the arrest (PPT) and the possibility that drugs might be found in the car. Conversely, if a person were arrested for shoplifting cigarettes and the officer decided to conduct a search of the person’s bag because the officer subjectively believed it might contain drugs (acting on the notion that “the person looked to me like a drug dealer”), the officer’s purpose for the search would not be objectively reasonable since it would not advance a criminal justice objective connected to the reason for the arrest.

(Note that in practical terms, this two-part test is relevant only where an accused raises an issue with whether a search was truly incidental to an arrest – and thus it does not arise in every case involving a search incident to arrest.)

– Search of phone or electronic device on arrest #

In Fearon, the Supreme Court held that police may search a cell-phone or electronic device incident to arrest on four conditions:

i. the arrest is lawful;

ii. the search is ‘truly incidental to the arrest’, meaning that it is carried out promptly and in order to advance one or more of the following law enforcement purposes: to protect the police, the accused, or the public; to preserve evidence; or to discover evidence—but a cellphone search on arrest for this third purpose is only justified “if the investigation will be stymied or significantly hampered absent the ability to promptly conduct the search” [para 80];

iii. the nature and extent of the search is tailored to the law enforcement purpose at issue (which in practice will generally mean “recently sent or drafted emails, texts, photos and the call log” but may reasonably include more, depending on the circumstances; and

iv. the police take detailed notes of what they examined on the device and how.

Police may conduct a search incident to arrest before the detainee has a chance to speak to a lawyer. (Debot)

– Strip search incident to arrest: #

Police are authorized to carry out a strip search following an arrest only where they have (in addition to the grounds for the arrest itself) “reasonable and probable grounds to believe it is necessary to carry out a strip search in the circumstances of the arrest” for (a) safety or (b) to prevent evidence from being destroyed. (Golden)

A reasonable strip search is one conducted at the police station in accordance with the guidelines set out in R v Golden, unless there are exigent circumstances.

Police may carry out a strip search in public or at the scene of the arrest only where they can establish that, in addition to having grounds for arrest and grounds for a strip search (described above), they have further reasonable grounds to believe that exigent circumstances make it necessary to carry out the search at that time and place for safety or to prevent the loss of evidence. (Golden)

2. Investigative Detention: #

At common law, police have a power to detain a person briefly for investigative purposes. A detention triggers a person’s Charter rights under sections 9 and 10(a) and (b). (Mann, Grant)

Police may carry out an ‘investigative detention’ when they have (a) a reasonable suspicion that the individual is implicated in the offence being investigated and (b) where the detention is reasonably necessary on an objective view of the totality of the circumstances. Factors to consider here include “the extent to which the interference with individual liberty is necessary to perform the officer’s duty [to investigate crime], the liberty interfered with, and the nature and extent of the interference.” (Mann)

There must be a clear nexus, based in evidence, tying the particular person detained to the offence being investigated (“individualized suspicion”). Courts will assess whether an officer had a ‘reasonable’ suspicion by considering the reasonable person in the officer’s position. (Mann)

An investigative detention triggers both 10(a) and 10(b). Police must inform the detainee, without delay, of the reason for the detention and their right to retain counsel. But police may briefly delay discharging their duties under 10(b) to carry out a safety search. (Grant, Suberu)

Investigative detention is distinct from what the Supreme Court has called “preliminary investigative questioning.” A person here is not detained and police are not obliged to advise them that they do not have to answer questions. (Suberu)

– Blockades #

The Court in Clayton held that police may set up a blockade and detain for investigative purposes persons if (a) doing so still involves individualized suspicion (or a nexus tying detainees to the offence being investigated) and (b) where it is reasonably necessary to do so based on the totality of the circumstances, including:

i. the nature of the situation (including the seriousness of the offence);

ii. the information known to the police about the crime and/or the suspects; and

iii. whether the stop/detention (i.e. geographic and temporal scope) is reasonably tailored to the offence, and in balancing the risk to the public versus the liberty of citizens, the stop is no more intrusive than is “reasonably necessary.” (Clayton)

An investigative detention should be brief, but may be as broad (in time or space) as is “reasonably necessary in the totality of the circumstances,” so long as its purpose is restricted to investigating the involvement in crime of particular suspects. (Clayton)

– Test for whether and when a ‘detention’ has occurred: #

In Grant, the Supreme Court set out a test for deciding whether a “detention” for the purpose of sections 9 and 10 has occurred. A person is “detained” where there is significant:

a. physical restraint, or

b. psychological compulsion.

-psychological compulsion is established where there is:

i. legal compulsion: where an officer makes a demand to comply pursuant to statute: eg, a roadside breath demand; or

ii. non-legal compulsion, which arises in circumstances where “police conduct would cause a reasonable person conclude that he or she was not free to go and had to comply with the police direction or demand.” [The test is purely objective.]

The Court in Grant held that whether the reasonable person subject to non-legal compulsion would conclude they were detained depends on the following criteria considered in their totality:

i. circumstances giving rise to the encounter as reasonably perceived by the individual [were they subject to general inquiries or singled out?];

ii. nature of the police conduct [language, duration, place, physical contact, presence of others, etc.];

iii. particular characteristics/circumstances of the individual [age, physical stature, sophistication, being a member of a racial minority].

The Supreme Court in Le held that under the 3rd part of this test, the reasonable person in the position of a racialized person is presumed to be aware of the “broader historical and social context of race relations between the police and various racial groups and individuals in society.”

In the broader ‘racialized context’ of a police encounter with a visible minority, it is irrelevant whether the police involved engaged in racial profiling when assessing whether the reasonable person would have experienced significant compulsion.

In a given set of circumstances, a racialized accused might be more likely than a white person to infer that they have no choice but to comply with a police direction or demand – and this inference may be reasonable in the circumstances, based on the weight of recent social science evidence.

The detention analysis in Grant and Le is principally objective in nature. (Evidence of what the police or the accused personally perceived is important, but not determinative of whether the factors pointing to psychological detention were, in their totality, significant.)

3. Search incident to Investigative Detention: #

At common law, police have a power to search incident to investigative detention, but it does not arise automatically upon a lawful investigative detention. Police must have separate or additional reasonable grounds to suspect that “officer safety, or the safety of others, is at risk.” (Mann)

This must be based on more than a mere hunch or a ‘personal intuition’ about safety (i.e., police must be able to point to evidence supporting their belief as reasonable). (Mann)

The scope of the search may extend no further than what is necessary to address concerns about safety. (Grant)

A note on standards: #

The common law makes the following distinctions on standards in criminal law:

  • suspicion’ would be something merely possible, even if its probability is low;

  • a ‘reasonable suspicion’ would be a reasonable possibility, or something not quite probable but more than hypothetical (SCC: Kang-Brown, Chehil);

  • reasonable grounds to believe’ and ‘reasonable belief’ have been held by the SCC in Debot and Baron to be synonymous with ‘reasonable and probable grounds,’ and each is a way of saying there is a reasonable probability of something3; and

  • balance of probability’ means greater likelihood or ‘more likely than not’.


  1. Section 34(1)(a) of the Interpretation Act defines an ‘indictable offence’ to include hybrid offences; see also R v Dudley, SCC 2009, applying this provision to the meaning of ‘indictable offence’ in the Criminal Code. ↩︎

  2. This summary excludes details pertaining to powers of arrest of property owners, and of civilians and police for breach of the peace. Briefly, contrary to other civilians, property owners may arrest a person they find committing a ‘criminal offence’ (see s. 494(2) for further qualifications). Breach of the peace is not an offence and involves actions that cause or are likely to cause harm to persons or property. Civilians may detain for breaches they witness (s. 30); police for this but also at CL for those immediately imminent (s. 31 and Thompson v Hayes, BCCA 1985; Brown v Durham, OCA 1998). ↩︎

  3. Some authorities have suggested the SCC decisions in Debot, Baron, and Storrey support the proposition that ‘reasonable and probable grounds’ means balance of probabilities or ‘more likely than not’. This is a plausible reading, but these cases have not explicitly endorsed this equation. The Court has held that RPG = reasonable probability, which means ‘likely’ rather than ‘possible’, and that RPG is ‘less than a prima facie case for conviction.’ The precise level of certainty for RPG remains unclear. For an example of a recent court decision outlining the state of this uncertainty, see paras 145-157 in Can v Calgary (Police Service), 2014 ABCA 322. ↩︎

© Robert Diab, TRU Law, 2022