top of page
  • ccsedu

The Interaction Between Federal Decriminalization and Provincial Prohibitions: A Summary of Murray-Hall v Quebec (Attorney General)

by Victoria Wright, J.D. Candidate 2025
Staff Writer, Seven/Fifty
January 31, 2024
Student protest Saskatchewan’s proposed pronoun legislation in Regina, Tuesday, Oct. 17, 2023. THE CANADIAN PRESS/Valerie Zink

In 2003, the Supreme Court of Canada (SCC) held in R v Malmo-Levine that protecting Canadian citizens from the health risks associated with cannabis is a valid criminal law purpose. Nearly two decades later, the decriminalization of cannabis in 2018 has opened the door to new provincial legislation on cannabis distribution and possession.[1] As a result, questions have arisen about the limits of provincial jurisdiction to regulate cannabis, some of which were recently addressed by the SCC in Murray-Hall v Quebec (Attorney General).[2]

In 2018, Parliament introduced the Cannabis Act (the federal Act) to decriminalize recreational cannabis in Canada, which included a prohibition on the possession and cultivation of cannabis plants for personal purposes.[3] However, the Cannabis Act exempted the possession and cultivation of no more than four cannabis plants from this general prohibition.[4] 

Importantly, the Cannabis Act also enabled provincial legislatures to regulate the sale and distribution of cannabis within their provinces.[5] In response, Quebec created the Société québécoise du cannabis (SQDC), which had a monopoly on the sale of cannabis in Quebec, and the Cannabis Regulation Act (the provincial Act), which contained several provisions regarding possession, cultivation, use, sale, and promotion of cannabis.[6] Sections 5 and 10 of the provincial Act completely prohibited any possession or cultivation of personal cannabis plants in a dwelling-house and had a penal sanction (a fine between $250 and $750) for failures to comply with the prohibition.[7]

Mr. Janick Murray-Hall (the appellant) challenged sections 5 and 10 of the provincial Act, arguing that sections 5 and 10 of the provincial Act fell within the federal criminal law power (section 91(27) of the Constitution Act, 1867) and were, therefore, ultra vires.[8] In the alternative, Mr. Murray-Hall argued that sections 5 and 10 of the provincial Act were of no force or effect due to the doctrine of federal paramountcy, which renders provincial laws inoperative to the extent that they conflict with federal laws.[9]

Validity: Are Sections 5 and 10 Ultra Vires the National Assembly?

To assess the validity of the provincial Act, the SCC characterized the provisions and then classified them by reference to the heads of power in section 91 and 92 of the Constitution Act, 1867. This is the standard way in which courts determine whether a challenged law is intra or ultra vires.

In characterizing sections 5 and 10 of the provincial Act, the SCC determined the pith and substance of the law by considering its purpose and effects.[10] The SCC noted that in characterizing specific provisions within a law, the impugned provisions must be interpreted “in light of their interaction with the scheme to which they belong.”[11] To determine the purpose of specific provisions and the law as a whole, consideration must be given to both intrinsic evidence (the actual text of the law, including its short and long titles) and extrinsic evidence (extra-textual sources such as parliamentary debates).[12] Extrinsic evidence sometimes indicates that the challenged legislation is colourable, meaning that it was designed to conceal an unconstitutional purpose. However, in Murray-Hall the provincial Act was not considered a colourable attempt by Quebec to recriminalize cannabis possession (as had been alleged), but rather an attempt to promote responsible consumption by steering citizens to SQDC outlets to obtain cannabis.[13] 

Ultimately, after considering the relevant evidence, the SCC held that the pith and substance of the provincial Act was to “ensure the effectiveness of the state monopoly in order to protect the health and security of the public, and of young persons in particular, from cannabis harm,” and that sections 5 and 10 “are a means of serving the public health and security objectives pursued by that Act.”[14] 

In Canada, criminal law is within the exclusive jurisdiction of the federal Parliament. Though sections 5 and 10 contained the three essential elements of a criminal law under federal jurisdiction (a prohibition, a penalty, and valid criminal law purpose such as protecting vulnerable groups from health risks associated with cannabis), the SCC classified sections 5 and 10 of the provincial Act as intra vires the Quebec legislature for several reasons.[15] 

Firstly, the SCC reaffirmed that the mere presence of a prohibition and penalty does not invalidate a valid exercise of provincial powers, such as creating a scheme to ensure that a state monopoly advances the objectives of public health and security.[16] This type of provincial scheme is grounded in provincial powers over property and civil rights (section 92(13) of the Constitution Act, 1867) and matters of a merely local or private nature in the province (section 92(16) of the Constitution Act, 1867).[17] It is important to note that the federal Act also effectively enabled provincial legislatures to enact prohibitions and penalties in relation to cannabis distribution and possession.[18] 

Secondly, as outlined in the SCC’s famous Margarine Reference decision, provincial legislatures can make laws and regulatory schemes that touch on valid criminal law purposes such as health.[19] As the Court stated, “the mere fact that the Quebec legislature considered the real risk that cannabis consumption poses for certain vulnerable populations when it enacted legislation is not in itself an indication of encroachment on the field of criminal law.”[20]

The ability for both the federal and provincial governments to create laws pertaining to cannabis distribution and possession can be explained by the double aspect doctrine. Contemporary views of federalism recognize that overlapping powers are unavoidable and the double aspect doctrine allows for concurrent jurisdiction on matters with compelling federal aspects and provincial aspects.[21] For example, laws pertaining to cannabis distribution and possession can concurrently address (1) criminal prohibitions (federal jurisdiction) and (2) health or trade regulations (provincial jurisdiction).[22] 

Operability: Do Sections 5 and 10 Frustrate the Purpose of the Federal Cannabis Act?

To assess the operability of the provincial Act, the SCC considered whether there was an operational conflict or if the purpose of the federal Act was frustrated.[23] When there is an operational conflict between federal and provincial laws or if the purpose of a federal law is frustrated by a provincial law, the doctrine of federal paramountcy applies.[24] This means that sections 5 and 10 of the provincial Act would be declared to be of no force or effect to the extent of their inconsistency with the federal Act.[25]

The SCC found that no operational conflict existed between sections 5 and 10 of the provincial Act and the federal Act as it is possible to simultaneously obey both laws.[26] The appellant conceded this point as Quebec citizens could comply with both acts by possessing and cultivating zero cannabis plants.[27] 

The SCC also found that the purpose of the federal law was not frustrated by the provincial Act —  rather, the objectives of the provincial and federal Acts are actually in harmony.[28] According to the SCC, the purpose of the federal Act was to limit organized crime, not to create a positive right to cultivate and possess cannabis.[29] The provincial Act is in harmony with the federal one because it reflects a closely related aim: to combat organized crime by creating a single market for the sale of cannabis.[30] Since the SCC did not find an operational conflict nor a frustration of federal purpose, sections 5 and 10 of the provincial Act were deemed to be operative.


The Murray-Hall decision reaffirms several important doctrines and principles of constitutional interpretation and provides another illustration of the SCC’s cooperative understanding of federalism, which allows both levels of government to create valid legislation in areas of overlapping jurisdiction. Moreover, since the SCC unanimously rejected the argument that the federal government could use the criminal law power to create positive rights, it effectively restrained the scope of the criminal law power. As a result, it is clear that valid criminal laws must take the form of a prohibition and penalty; if the federal government wants to create laws prescribing positive rights, they have the means to do so under other federal heads of power.


[1] Murray-Hall v Quebec (Attorney General), 2023 SCC 10.

[2] Ibid.

[3] Ibid at para 4.

[4] Ibid at para 4.

[5] Ibid at para 5.

[6] Ibid at para 6.

[7] Ibid at para 7.

[8] Ibid at para 8.

[9] Ibid at para 8.

[10] Ibid at paras 23-24.

[11] Ibid at paras 30-31.

[12] Ibid at para 25.

[13] Ibid at paras 48-57.

[14] Ibid at para 28.

[15] Ibid at paras 65-69.

[16] Ibid at paras 68-71.

[17] Ibid at para 71.

[18] Ibid at paras 68-71.

[19] Ibid at para 69.

[20] Ibid at para 69.

[21] Ibid at para 76.

[22] Ibid at para 77.

[23] Ibid at paras 83-84.

[24] Ibid at para 83.

[25] Ibid at para 83.

[26] Ibid at para 87.

[27] Ibid at para 87.

[28] Ibid at para 104.

[29] Ibid at para 90.

[30] Ibid at para 103.

44 views0 comments


bottom of page