Introduction
Canadian law and politics scholarship has afforded significant attention to interinstitutional relationships between courts and governments in the post-Charter era. However, scarce attention has been paid to government legal mobilization—that is, the ways in which governments strategically participate in the courts to achieve their goals. Government legal mobilization can take several forms; commonly, however, governments “intervene” in cases at the Supreme Court of Canada (SCC) (Hausegger et al. Reference Hausegger, Hennigar and Riddell2015). Intervention is a mechanism which allows governments, organizations and individuals to apply to make arguments in legal cases that they are not direct parties to (McNabb Reference McNabb2023; Callaghan Reference Callaghan2020).
In this article, we build upon earlier work by Hennigar (Reference Hennigar2010) and Radmilovic (Reference Radmilovic2013) to update the literature on government interventions. As these studies only provide coverage of cases up to 2007 and focus exclusively on disputes involving the Charter of Rights and Freedoms (Charter), it remains unknown whether governments’ intervening behaviour in Charter cases can be generalized to other types of constitutional disputes. Likewise, the temporal gap in the literature matters because there have been subtle changes to the intervening landscape at the SCC over the past decade.Footnote 1 Therefore, through an empirical assessment of government interventions in all constitutional cases heard by the SCC between 2013 and 2023 (n = 164), our work makes a significant contribution to the study of government legal mobilization in Canada.
Hennigar (Reference Hennigar2010) and Radmilovic’s (Reference Radmilovic2013) Studies
In an early study of government interventions, Hennigar (Reference Hennigar2010) examined the conditions under which the federal government concedes that a federal law or regulation violates the Charter. As Criminal Code offences are typically enforced by provincial Crown prosecutors, this means that the attorney general of Canada often has to intervene to make arguments in the SCC about its own laws. From a content analysis of 139 facta submitted by the federal government in SCC Charter cases decided between 1984 and 2004, Hennigar finds that interventions are almost always initiated to protect legislation against threats to its constitutionality.
The scope of Hennigar’s work was expanded in Radmilovic (Reference Radmilovic2013), which analyzes all government interventions across all SCC Charter cases (252) involving judicial review of legislative and regulatory acts between 1982 and 2007. The study similarly found that governments overwhelmingly intervene “defensively,” where submissions are used to encourage the Court to uphold the constitutionality of legislation (93% of submissions) (Reference Radmilovic2013: 327). Additionally, Radmilovic found that the Court “saved legislation” in roughly two-thirds of cases, concluding that the Court is influenced by government interveners in a systematic and significant manner (Reference Radmilovic2013: 324). The study also reports that intervening governments typically provide arguments in support of the same side of the dispute (Radmilovic Reference Radmilovic2013: 328). While these studies demonstrate that governments are generally unified in Charter cases and use intervention to defend their legislation, it is unclear whether government interveners behave similarly in other types of constitutional disputes, such as cases dealing with federalism and intergovernmental conflict.
Data and Methods
To update and expand upon the work of Hennigar and Radmilovic, we created an original dataset of all government interventions in SCC constitutional cases decided between 2013 and 2023.Footnote 2 Our dataset includes cases involving the division of powers (DoP), Aboriginal and Treaty rights, Charter claims and other constitutional matters.Footnote 3 Through a content analysis of the written submissions of government interveners, our study addresses the following research questions:
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1. Which governments intervene in constitutional cases and how often?
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2. Are government interventions in constitutional cases offensive (asking the Court to declare a law or action as unconstitutional), defensive (asking the Court to declare a law or action as constitutional) or neutral (not clearly supporting one side of the dispute or presenting a clear preference on the outcome)?
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3. Do governments intervene as a unified front in constitutional cases?
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4. How successful are governments when they intervene in constitutional cases?
Findings
Across the 164 constitutional cases heard by the SCC between 2013 and 2023, at least one government intervened in 78 per cent of these cases, for a total of 408 interventions, and an average of three government interveners per case.Footnote 4 Governments intervened in 74 per cent of Charter cases during this period, which is similar to the earlier period covered by Radmilovic (1984–2007), where governments intervened in 80 per cent of Charter cases.
As seen in Tables 1 and 2, there is variation in the rate of government interventions across different areas of constitutional law, and in the frequency that specific governments intervene. Although Charter cases make up the largest proportion of constitutional cases, these cases have the lowest rates of government participation. This should not be surprising, as Charter cases include routine criminal justice appeals such as trial delays. In contrast, governments intervened in every single Aboriginal and Treaty Rights case, reflecting how these cases distinctly impact government power. With respect to individual government participation, our findings deviate from Radmilovic (Reference Radmilovic2013), which may reflect our broader focus on all constitutional cases and/or shifts in governments’ priorities. For instance, Radmilovic (Reference Radmilovic2013) found that Ontario and Quebec intervened at similar rates. However, our study demonstrates that in recent constitutional cases, the attorney general of Ontario has intervened nearly twice as often as the attorney general of Quebec. Similarly, we find that the attorney general of Alberta intervenes more than the attorney general of British Columbia, whereas Radmilovic (Reference Radmilovic2013) found these governments to intervene at similar rates.
Table 1. Overview of Constitutional Cases at the Supreme Court of Canada (2013–2023)

Table 2. Government Interventions in Constitutional Cases at the SCC (2013–2023)

Table 3 summarizes the distribution of government submissions with a defensive, offensive or neutral position. Government preferences were distilled through a qualitative reading of written submissions; 4 per cent of government interventions were neutral, where the government did not clearly support one side of the dispute or have a clear preference on the outcome.Footnote 5 Consistent with the work of Hennigar (Reference Hennigar2010) and Radmilovic (Reference Radmilovic2013), we find the vast majority of government interventions to be defensive. Specifically, 94 per cent of interventions in Charter cases are defensive, which is nearly identical to the 93 per cent rate reported by Radmilovic (Reference Radmilovic2013). Offensive interventions were far less common, making up just 11 per cent of all interventions. Most offensive interventions were in reference cases (90%) and/or DoP cases (70%).Footnote 6 Although 41.7 per cent of interventions in DoP cases were offensive, this varied on the basis of whether federal or provincial legislation/action was at issue. When a federal law or action was challenged, 75 per cent of interventions were offensive (24/32). However, when a provincial law or action was challenged, only 12.8 per cent of government interventions were offensive (5/39).
Table 3. Interventions by Position and Constitutional Issue (2013–2023)

Table 4. Success Rates across Government Interveners (2013–2023)

To evaluate the extent to which governments appear as a unified front before the Court, the next part of our analysis turned to the 91 cases where more than one government intervened. We found that in 85.7 per cent of these cases, all government interveners submitted arguments that support the same “side” of the dispute. Radmilovic found a slightly higher rate of uniformity in government arguments (92.5 per cent), but this likely reflects his narrower and exclusive focus on Charter cases. Indeed, our study shows that government disagreement is most common in DoP cases.
In Table 4, our analysis considers whether governments are successful in their interventions. Consistent with the broader legal mobilization literature, we define success as the Court making a ruling on the outcome in favour of whichever side a government supports through their intervention.Footnote 7 Governments were successful in 54.5 per cent of their interventions, meaning that their interventions only resulted in favourable outcomes from the Court about half of the time. Of the governments that intervene most frequently, the attorney general of Ontario comes out ahead, with a success rate of 64.5 per cent. Thus, the attorney general of Ontario not only intervenes the most frequently, but also enjoys the most success in doing so, consistent with Galanter’s “haves and have nots” theory (Reference Galanter1974), which posits that repeat players in court have better odds at winning (relative to “one-shotter” litigants). At the same time, success rates vary across provinces with similar rates of intervening. For example, the attorney general of Quebec is successful in 53.3 per cent of cases, while the attorney general of Alberta, who intervenes at a similar rate, is most often on the losing side of the dispute (48.1 per cent success rate). Interestingly, there are multiple provinces with a higher success rate than the federal government. This finding is particularly important as it runs counter to previous scholarship that suggests the federal government generally enjoys more success at the SCC compared to the provinces (Brouillet Reference Brouillet, Kincaid and Aroney2017; McCormick Reference McCormick1993).
Conclusions
This article sought to update and expand upon the work of Hennigar (Reference Hennigar2010) and Radmilovic (Reference Radmilovic2013) on government interventions to enhance our understanding of government legal mobilization in Canada. On the whole, the findings of Hennigar and Radmilovic pass the test of time and still provide an accurate, empirical account of government interventions in Charter cases. We find that between 2013 and 2023, governments still overwhelmingly intervene in Charter disputes to defend their laws. Likewise, similar to Radmilovic, our study shows that governments frequently intervene in support of the same side of the dispute.
Importantly however, by looking beyond the Charter, our findings reveal complexity in how governments intervene across constitutional cases, which was not captured in these earlier studies. Perhaps most notably, our study shows that government interveners behave distinctly in division of power cases and reference cases. As these cases tend to pit different orders of government against one another, our findings reveal that governments frequently intervene offensively. Similarly, despite a high degree of uniformity in all other types of constitutional cases, governments are often divided within DoP disputes. Future work should extend this analysis to evaluate patterns of government interventions in non-constitutional cases at the SCC.
Acknowledgements
The authors wish to thank the CJPS editors and anonymous reviewers for their helpful feedback. We also wish to thank Matthew Hennigar and Emmett Macfarlane for providing constructive comments on an earlier draft, and Paul Gardner for providing advice and support in the earlier stages of this project.
Competing interests
The authors declare none.