Detention vs. Arrest: What Are Your Rights?

So, you’ve been stopped by the police. Are you being detained or arrested? What’s the difference and why is it important? What can the police do and not do in each scenario? This article will explain, in broad terms, what a detention is, what an arrest is, and what can and cannot happen during either circumstance.


If the police have stopped you and either physically or psychologically keep you from leaving, they are detaining you. A physical detention is pretty clear, but a psychological detention is not always as obvious. The general rule was created in the Supreme Court of Canada decision in R v Grant, 2009 SCC 32, and explains that psychological detention begins when:

  1. someone is under a legal obligation not to leave.  For example, if they say “don’t leave” or at a traffic stop; or
  2. if a person would reasonably believe the choice to leave or walk away from the officer was no longer available. For example, an officer asks “what are you up to tonight” but has blocked the only exit from where you are.

In each case, how a reasonable person would react or respond to the police is specific to the context in which the psychological detention occurred. Some of the factors include: the cause of the interaction with the police; the feeling of being singled out; the tone the police use when addressing you; the words they use; and your own personal circumstances. In the case of R v Grant, the detention began when, in the course of asking Grant what he was up to, the police told him to keep his hands where they could see them. To take a common example, asking for your ID is not a form of detention, but taking your ID to conduct a search of the police databases has been ruled as a form of psychological detention in some cases.

It is important to determine if a detention has actually occurred, as there are certain rights and rules that need to be followed if a person is being detained. Two rights under Canada’s Charter of Rights and Freedoms, section 9 and section 10(b), are automatically triggered by a detention. Section 9 is the right not to be arbitrarily detained, which means that the police must have a reason to detain you for the purposes of investigation. They need to state why they are detaining you, and they must have a reasonable suspicion or purpose for the detention. 

The police can stop you for one reason but then continue the detention if other suspicions arise. An example would be a traffic stop, which is generally one of the most common. Let’s say the police pull you over. They tell you that they are doing so because you were driving in a manner they consider to be dangerous. They suspect you may be impaired. They run your name, plates and registration and begin to suspect you are doing some other illegal activity. So long as they inform you of the new reasons for detention, the police can continue the investigative detention based on those new suspicions.

Any detention must be based on more than just a hunch. In R v Harrison, 2009 SCC 34, the accused was pulled over in Ontario in an SUV with no front license plate. After pulling the vehicle over, the officer saw that it was from Alberta where a front plate is not required. He ran the plate and found it had been rented from the Vancouver airport which raised his suspicions. At this point, the driver should have been let go. Instead, the officer followed his hunch and continued to detain the man. The Supreme Court of Canada ruled that the stop had no merit and any evidence found post detention was inadmissible.

The other Charter right that is triggered by detention is section 10(b), the right to counsel. Section 10(b) states that everyone has the right on arrest or detention to retain and instruct counsel without delay and to be informed of that right. What that means is that even at this stage, prior to any charges being laid, you have the right to speak to a lawyer immediately. 

Breaches of either of these Charter rights have been seen as enough to acquit or stay proceedings; however, that is not always guaranteed. Once again, this is decided on a case-by-case basis and is affected by the context and circumstances of each.

Section 9 also dictates the length of the detention. The courts have stated the detention should be brief. Of course, what constitutes “brief” will vary in each circumstance, but it must not be longer than is necessary for the investigation. If the detention is seen as longer than necessary, it can be viewed as a de facto arrest.

Charter rights also come into play with respect to what an officer can do during detention. Section 8 of the Charter protects against unreasonable search and seizure. During an investigation, the police are allowed to search your person, but such search must only be for the purposes of the safety of the officers and not for the collection of evidence. Generally, a pat down to feel for any potentially harmful objects is allowable, but reaching into pockets is not. In R v Mann, 2004 SCC 52, the police conducted a pat down, did not feel anything that could be a weapon, but did feel a soft bag inside a coat pocket. The officer reached in and discovered a bag of cannabis and the accused was arrested for possession. It was ruled that when the officer reached inside the pocket to find the bag, it was a search for evidence and not for safety purposes, resulting in the violation of the individual’s section 8 Charter rights. Contrary to popular belief, there is no general power to search bags or vehicles during a detention. This does not mean the police cannot look inside your vehicle, but they must only examine what is clearly seen from outside the vehicle. They cannot ask you to move things so they can have a better look, nor can they open a door or stick their heads inside.

Lastly, in all cases, once the police have concluded their investigation, they must clearly state that you are allowed to leave if they do not arrest you.


If an officer does choose to arrest you, the arresting officer must have reasonable and probable grounds for the arrest. This means that a reasonable person with the same training would agree that the arrest should happen. Further an arrest must be based on evidence and knowledge that was known to the officer prior to the arrest. They cannot arrest first and then make a decision as to the grounds after. While the police can use knowledge provided to them by third parties, that information must be based on more than a hunch or an action that would be seen as lawful without other evidence to the contrary. For example, if the police were provided with the information that the accused was seen exchanging a box but there was no further evidence that this person may be involved in illegal activities, this information would be insufficient for an arrest.

Once you have been placed under arrest, the police must inform you of the reason. They must also read or recite to you the rights and warnings, which includes a right to call a lawyer, even if you were given that chance while being detained, and the right not to have to speak to the police.

Once an arrest has been made, the police do have a heightened ability to conduct searches. The officer is given considerable discretion for the search as long as the reason for the search is valid and truly incidental to the arrest. There are 3 grounds that most searches are based on:

  1. To ensure police or public safety;
  2. To protect evidence; and
  3. To discover evidence.

In most circumstances, an accused who has been arrested has no reasonable expectation of privacy with respect to personal belongings. This means that searches of things like pockets and bags are allowed. Searches of vehicles, including the trunk and bags found within, are generally allowed after an arrest but there must be a valid reason for the search connected to the arrest. For example, if you are pulled over for speeding and are arrested for a breach of a release order by not being in your residence during prescribed hours, the police have no valid reason to search your vehicle.

In conclusion, in any criminal case, one of the first things we look at is the detention and arrest. If the detention and/or arrest are invalid, or there were any other breaches of Charter rights, then there are any number of remedies available, from exclusion of evidence to lessening a sentence to the case being dropped. The same applies for searches that are shown to be unlawful. Each case is different and determining any of the above needs to be done on a case-by-case basis. Due to the nuances of individual circumstances, this can become a very technical and legal argument that many times is decided by a judge after hearing both sides. Having a lawyer to help you navigate this is crucial.

If you are seeking legal representation and would like to discuss your file, the lawyers at Lakefield LLP would be more than happy to talk to you.

The information in this article does not constitute legal advice. The law may have changed since this article was first published. You should consult with your lawyer to confirm the current state of the law and obtain advice specific to your situation.