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What happened in Dedman v The Queen?

In 1985, the Supreme Court of Canada’s ruling in Dedman v The Queen created an important legal precedent that facilitated the expansion of common law police powers in Canada.

The issue before the Court in Dedman was whether the police had lawfully stopped Dedman’s car during a checkstop program (at paragraph 50). The Court adopted the Waterfield test from an earlier British case to assess whether the police conduct in question was within the scope of police powers and whether it was lawfully executed (at paragraph 68). Because there was no existing legislation to provide the Court with guidance on the matter at hand, the Court looked to pre-existing common law police powers, such as crime prevention and protection of life, to determine that the control of traffic through a random checkstop was a lawful exercise of police power (at paragraph 68). By repurposing and then applying the Waterfield test to the facts before them, the Court in Dedman created a new ancillary police power that could be utilized by police in the exercise of their duties and relied on by judges in future cases (at paragraph 69). 

Why does Dedman stand out as an important case in Canadian law?

Although the Waterfield test had been used in Canadian courts prior to Dedman (Knowlton v The Queen at page 446), Dedman was the first instance of a court using the test  to create a new police power. This, experts have argued, was a pivotal shift in the law which would allow judges to review police conduct retroactively and decide whether that conduct was lawful or not, leaving citizens without fair notice of the law during an encounter with the police. 

The Waterfield test, as developed in Dedman, ultimately provided judges with a tool that could be used in future cases to generate new ancillary police powers whenever there is a gap in the existing legislation. The ruling in Dedman, therefore, became a watershed moment that had ripple effects in this area of the law.


What happened after the ruling in Dedman?


After Dedman, courts in most provinces and territories have used the Waterfield test to create new ancillary police powers and to deploy (apply) existing powers to similar cases. This has greatly expanded common law police powers in Canada.


As we have highlighted here, police powers have been generated and deployed around multiple jurisdictions for the past 35 years. Historical trends suggest that, once generated, these powers have been deployed at ten times the rate that a new power is generated.


Once a police power is generated, that power becomes constitutionally protected and can be deployed by courts in the future.


Deployment of common law police powers has occurred in much more frequency than generation of these powers.


Deployment of police powers occurred 161 times between 1985 - 2001 and 732 times between 2002 - 2017.


Since the ruling in Dedman, close to 10 deployments of police powers occur for every generation of a power that takes place.

The facts and statistics below provide a stark picture of the generation and deployment of ancillary police powers in the Canadian legal system since the ruling in Dedman


In 1985, the Supreme Court of Canada created a new common law police power which changed the legal landscape in relation to police powers for the next 35 years.

Image by Benoit Debaix

The House of Commons and provincial legislatures create legislation that gives powers to police in the exercise of their duties.

Some justices of the Supreme Court of Canada disagreed with majority decisions that ruled on expanding judge-made police powers.


Chief Justice Brian Dickson served on the Supreme Court from 1973 - 1990. In the early years of Charter rulings, the Supreme Court emphasized the importance of the right to privacy and right not to be arbitrarily detained.

Former Chief Justice Brian Dickson was part of the Court that oversaw much of the early Supreme Court of Canada jurisprudence (legal philosophy) dealing with the Charter and police powers. In the early years, Chief Justice Dickson stated that the judiciary must act as the "guardian of the constitution" (Hunter v Southam at page 155).


In Dedman, Dickson dissented (had a differing legal opinion) from the majority decision and stated that the checkstop program was an arbitrary use of police detention powers and unlawfully interfered with individual liberty. (Dedman at paragraph 25)


Justice Louis LeBel served on the Supreme Court from 2000 - 2014. In this period, the Court expanded police powers in the area of sniffer dogs, investigative detention and cellphone searches, among other powers.

Justice Louis LeBel (along with Justice Morris Fish), who served on the Supreme Court during a period which saw an increase in the generation and deployment of common law police powers, argued for judicial restraint in this area of the law (R v Kang-Brown, at paragraph 14). Justice LeBel echoed Justice Dickson's earlier warnings by bringing attention to the conflict of interest involved when the courts are making laws that restrict constitutional rights and values on one hand and are guardians of these same rights and values on the other. (Kang-Brown at paragraph 12).

what happened?
Why does dedman stand out?
What happened after the ruling?


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