Introduction
Canada’s notwithstanding clause is back. The clause allows legislatures to declare that laws operate notwithstanding judicial review for compliance with certain sections of the Canadian Charter of Rights and Freedoms. After 30 years of relative neglect, it has been invoked in six different provincial laws since 2018. The current Conservative Leader of the Opposition, Pierre Poilievre, has pledged to enact what would be the first federal use of the notwithstanding clause (Thompson, Reference Thompson2024). What explains the resurgence of the notwithstanding clause?
In this article, we first contextualize the revival of the notwithstanding clause by reviewing its origins as a mechanism desired by provincial governments to mitigate the centralizing tendencies of the Charter. The history of the notwithstanding clause serves as a reminder that one of the main reasons for concern about a centralizing Charter was the federal constitutional monopoly on the power to appoint judges to all federal and provincial superior courts—a monopoly that remains intact today. We then draw from an original dataset of every Supreme Court of Canada Charter case from 1982–2020, reviewing the constitutionality of provincial and federal statutes for Charter compliance.
Using within-case process tracing and data analysis, we show how provinces have begun using the notwithstanding clause during a period in which the Supreme Court has invalidated a higher proportion of provincial laws. This period has also coincided with partisan conflicts between a Liberal federal government (elected in 2015) and conservative provincial governments, and with conservative voters manifesting a growing skepticism towards judicial power (Lawlor and Crandall, Reference Lawlor and Crandall2023). We argue that the resurgence of the notwithstanding clause is best explained by a strategic environment where partisan federalism conflicts lower the political costs of using the clause, while rising invalidation rates incentivize provinces to use it to protect their jurisdiction. This new strategic environment has shifted the previously path-dependent disuse of the clause to a new path where conservative provincial governments experience increasing partisan returns when they use the clause to protect their policy preferences from invalidation by federally appointed courts. This “new” provincial-rights justification for the notwithstanding clause largely mirrors the justification put forward by its main proponents when the Charter was created (Newman, Reference Newman, Sigalet, Webber and Dixon2019: 219).
This article makes several empirical and theoretical contributions. In the Canadian context, it provides an empirical explanation for the revival of the notwithstanding clause outside the province of Quebec. While others have argued that concerns over Charter centralization were overblown (Kelly, Reference Kelly2001; Baier, Reference Baier, Macfarlane and Puddister2022), our theoretical claim is that the Charter’s centralizing tendencies are evident in how provinces have attempted to constrain judicial power under certain strategic conditions. This theory may also help explain why the federal Parliament is less likely to use the notwithstanding clause despite high invalidation rates at the federal level, because it strategically benefits from and constrains judicial power in ways the provinces do not.
Comparatively, this study can help enrich theories of the relationship between “weak-form” judicial review and federalism (Tushnet, Reference Tushnet2008) by explaining why judicial interpretive finality may be more likely to be contested by divergent partisan agents at the subnational level. Our analysis also offers empirical evidence for the “regime politics” (Hirschl, Reference Hirschl2004; Whittington, Reference Whittington2005) view that partisan regimes tolerate judicial power over constitutional rights in federal systems partly as a means of imposing centralizing standards on substate actors. Finally, this study contributes to the literature on “court curbing” insofar as we conceptualize how partisanship impacts the notwithstanding clause as a “soft” formal instrument for constraining judicial behaviour without attacking judicial institutions (Gardner and Thrower, Reference Gardner and Thrower2023; Clark, Reference Clark2009; Vanberg, Reference Vanberg2005; Lawlor and Crandall, Reference Lawlor and Crandall2023).
In what follows, we begin with a review of the literature on the notwithstanding clause and the “centralization thesis” to re-situate the understanding of the clause as a mechanism to limit the Charter’s centralizing tendencies. We then use within-case process tracing (Collier, Reference Collier2011) to trace the history of the notwithstanding clause, showing how, after three decades of minimal use, its political rebirth since 2018 has coincided with a growing conservative provincial rights movement. We then provide empirical evidence showing how the clause’s revival has also coincided with increasing Supreme Court invalidations of provincial statutes since 2010. We close with an analysis of the centralizing strategic environment facing provinces and a discussion of how this theory enhances our understanding of several concepts essential to the political study of judicial review.
Charter Centralization and the Notwithstanding Clause
Scholars have long been interested in the way courts can facilitate centralization or decentralization within a federal state. André Bzdera (Reference Bzdera1993: 24) argued that judicial review had a centralizing effect in nine federal states, and suggested that this “net centralist/nationalist bias of federal high courts” can be explained in part by nationalized administration processes and federal appointment power. Likewise, Martin Shapiro’s comparative study found federal judiciaries with a final national court of appeal tend to “serve upper class and nationalizing interests rather than dominant local interests and thus [are] more satisfactory to persons trying to break through the web of local interests” (Reference Shapiro1981: 24).
Ran Hirschl (Reference Hirschl2004) has tied this thesis explicitly to the entrenchment of bills of rights as a way for hegemonic elites to use minoritarian courts to preserve their policies and interests in the face of new electoral competition. In the American context, regime politics approaches have emphasized how judicial review is empowered by winning “the approval of national officials by imposing their shared constitutional agenda on recalcitrant state actors who hamper national political goals” (Whittington, Reference Whittington2005: 586). These studies are complicated by comparative evidence that federal courts can facilitate integration and compliance with a common regulatory regime (Carrubba, Reference Carrubba2009), while also being constrained by threats of legislative override or non-compliance from member states (Carrubba et al., Reference Carrubba, Gabel and Hankla2008). More recently, Aroney and Kincaid (Reference Aroney and Kincaid2017) argue the evidence for centralizing federal courts is “mixed,” though “leaning in the direction” of centralization (483).
While Canada is generally recognized as one of the most decentralized countries in the world, its judicial structure is not. All judicial decisions—including those involving provincial law—can ultimately be appealed to the Supreme Court of Canada. The federal government also has an outsized role in appointing judges; it appoints judges to the Supreme Court of Canada, federal courts and provincial “superior” courts (provincial courts of appeal and the courts directly below them). Since the Supreme Court of Canada became Canada’s final court of appeal in 1949, there has been a vigorous debate regarding whether its federalism jurisprudence has had a centralizing influence. Some argue the Court has struck an appropriate balance (Baier, Reference Baier2006; Russell, Reference Russell1985), while others suggest the Supreme Court has adopted a “trend towards centralization” (Brouillet, Reference Brouillet, Aroney and Kincaid2017: 163; see also Leclair, Reference Leclair2023). Notably, few if any scholars in Canada have made the argument that the Supreme Court has been decentralizing (as its predecessor the Judicial Committee of the Privy Council was).
Most comparative accounts of centralization typically focus on high courts’ jurisprudence concerning the federal division of powers—and with good reason, for that is the most obvious area for which a court can make determinative decisions about jurisdictional boundaries and the allocation of heads of power. However, as Hirschl’s work (2004) shows, debates over the centralizing effect of judicial power have gone beyond federalism, and this is particularly true in Canada. Indeed, when Canada passed its constitutional bill of rights, the 1982 Canadian Charter of Rights and Freedoms, there was a spirited debate regarding the extent to which it would be a centralizing document.
It is uncontroversial to note that the Charter was advocated by Prime Minister Pierre Trudeau as a centralizing “pan-Canadian” instrument to provide Canadians with a national symbol to secure an identity tied to equal rights guaranteed across provincial and federal jurisdictions (Schertzer, Reference Schertzer2016: 41-21; Russell, Reference Russell1983; Reference Russell2004: 111; Hirschl, Reference Hirschl2004). To protect provincial legislative power, Alberta Premier Peter Lougheed, Saskatchewan Premier Alan Blakeney and Manitoba Premier Sterling Lyon subsequently made a “notwithstanding clause”—which would allow legislatures to enact laws that would operate notwithstanding the judicial review of certain Charter provisions—a condition of their agreement to the Charter. The notwithstanding clause became the main expected mechanism for resisting potentially centralizing judicial activism under Canada’s Constitution Act, 1982.
Political scientist Peter H. Russell predicted the Charter would have a unifying effect on Canadian public policy. Rejecting the “disavowals of any centralizing implications of the Charter” made by then-Justice Minister Jean Chrétien, Russell expected the Supreme Court to act as “a kind of national Senate reviewing the reasonableness of provincial laws and policies” (Russell, Reference Russell1983: 42). Within a decade, several scholars argued that Russell’s prediction had come to fruition. Cairns (Reference Cairns1992) noted how the Charter had empowered “Charter Canadians,” a new coalition of social interests with progressive (and crucially, non-territorial) policy preferences seeking to use the Charter to constitutionalize their goals. Morton similarly argued that the “net effect” of the Charter was “a change in institutional structure that privileges the resources of selected, nonterritorial social interests… for the provinces, this translates into a structural loss of policy autonomy” (Reference Morton1995: 183). This perspective came to be known known as the “centralization thesis.”
Others challenged the centralization thesis. Janet Hiebert (Reference Hiebert, Douglas and Hiebert1994: 163-71) claimed the Supreme Court had shown a willingness to accept provincial differences as a justification of “reasonable limits” on Charter rights. Russell himself found that the Supreme Court’s first decade had resulted in a greater invalidation of federal statutes than provincial ones (Russell, Reference Russell1994: 37-38). Most notably, James B. Kelly undertook an empirical review of Supreme Court decision making and argued that the Charter “has not unduly undermined provincial autonomy” (Reference Kelly2001: 324). Kelly argued that structural components of the Charter itself—particularly the reasonable limits and notwithstanding clauses—contributed to provincial autonomy. However, his main argument was that the Supreme Court’s jurisprudence had “advanced federal diversity” because of the Court’s demonstrated “sensitivity” to provincial policy variation and to “the structural requirements of a federal system” (324).
Since Kelly’s (Reference Kelly2001) study, there has been minimal scholarly re-evaluation of the centralization thesis, and no empirical analyses. Clarke (Reference Clarke2006: 311) claims the Supreme Court had created a “federalist dialogue” that permits provincial variation on rights; Baier (Reference Baier, Macfarlane and Puddister2022: 66) suggests centralization has been “tepid” at most; and Harding (Reference Harding, Macfarlane and Puddister2022: 26) argues that the Court’s interpretation of the Charter has had some homogenizing effects, but that centralization has not been as “totalistic” as Morton and others predicted. The notwithstanding clause—which was supposed to be the instrument designed to prevent Charter centralism—has played a background role in the debate over the centralization thesis.
Tracing the Fall and Rise of the Notwithstanding Clause
The text of Canada’s notwithstanding clause was written to allow legislatures to enact laws “notwithstanding” certain important sections of the Charter. The clause applies to the fundamental freedoms of section 2, the legal rights of sections 7–14 and the equality rights of section 15. This prevents the clause from being invoked in relation to democratic rights (sections 3–5), mobility rights (section 6) and language rights (sections 16–23). Although there has been recent debate about the technical legal effect of the clause (Sigalet, Reference Sigalet2024; Webber, Reference Webber2021), the clause clearly protects laws from being struck down by courts for violating certain Charter provisions for renewable five-year periods.
The first years of the Charter appeared to hearten proponents of the notwithstanding clause as a bulwark against centralization, at least in the province of Quebec. In 1982, to protest the fact that the Constitution Act, 1982 was enacted without the consent of its government, Quebec’s National Assembly passed a law that repealed and replaced every Quebec law with an identical statute invoking the notwithstanding clause. This “omnibus” use of the notwithstanding clause continued with every new Quebec bill from 1982 to 1985, until the governing Parti Québécois was defeated by Robert Bourassa’s Parti libéral du Québec, whose government still invoked the clause in ten new pieces of legislation between 1986–1988.
In addition to Quebec’s “omnibus” use, the notwithstanding clause has been invoked in 23 unique provincial statutes since 1982 (excluding renewals). However, these overall numbers belie the fact that the use of the clause has varied over three historical periods. Table 1 organizes these uses by historical period and includes renewals in parentheses. Between 1982–1988, the clause was used vigorously by Quebec and was also invoked once each by the province of Saskatchewan and the Yukon Territory. From 1989–2017, there were far fewer new laws invoking the clause (four new statutes in Quebec and one in Alberta), although Quebec frequently renewed its existing invocations of the clause. Rousseau and Côté (Reference Rousseau and François Côté2017) have convincingly argued that Quebec’s use of the notwithstanding clause from 1982–2017 reflects a distinct political and legal culture compared with the rest of Canada, as Quebec also frequently invoked its provincial equivalent of the notwithstanding clause to insulate laws from its Charte des droits et libertés de la personne during this period.
Table 1. New Laws Invoking the Notwithstanding Clause Over Time (Renewals in Parentheses)*

*This table distinguishes between new uses of the notwithstanding clause and renewals of existing laws invoking the clause. Drawing from Kahana (Reference Kahana2023) and Lawlor and Crandall (Reference Lawlor and Crandall2023), we count 49 renewals including Quebec’s 2024 renewal of its An Act respecting the laicity of the state. We follow Kahana’s (Reference Kahana2023) and Nicolaides and Snow’s (Reference Nicolaides and Snow2021) methodology for counting new uses of the clause, which includes “statutes into which notwithstanding declarations were inserted rather than the statutes that did the act of inserting” (Kahana Reference Kahana2023: 8); includes all bills that received royal assent including those that did not come into force; but excludes bills invoking the clause that were never passed. For alternative selection criteria, see Rousseau and Côté (Reference Rousseau and François Côté2017) and Lawlor and Crandall (Reference Lawlor and Crandall2023).
Since 2018, the clause has come back into prominence, with six new provincial laws passed invoking the clause in six years. The federal Parliament has never used the notwithstanding clause, although it has been unsuccessfully invoked in private members bills, including a bill put forward by the Bloc Québécois in 2024 on criminal trial delay.Footnote 1
To understand why the clause fell into relative disuse for nearly 30 years after 1989, it is necessary to understand Canada’s constitutional context in the 1980s. Quebec was the only province whose government did not agree to the Constitution Act, 1982. The constitutional agreement was viewed as a betrayal by many within la belle province—hence the omnibus use of the notwithstanding clause from 1982–1985. The 1987 Meech Lake Accord, a series of decentralizing amendments to the Canadian Constitution including recognition of Quebec as a “distinct society,” was designed to get Quebec to “sign on” to the Constitution. With respect to the courts, the Accord would have added a new section to the Constitution Act, 1867 requiring the federal government to select Supreme Court justices from lists submitted by the provinces. In the minds of the provincial premiers who signed Meech, de facto provincial selection of Supreme Court judges would have helped mitigate Charter centralization.
However, in December 1988, the Supreme Court of Canada ruled in Ford v. Quebec (1988) that the province’s French-only sign law was an unreasonable violation of the Charter right to freedom of expression. Quebec’s National Assembly responded by passing Bill 178, which invoked the notwithstanding clause to mandate French on outdoor signs while permitting other languages on indoor signs. Quebec’s invocation of the notwithstanding clause in response to the Supreme Court decision was met with widespread condemnation by political leaders outside Quebec. The Meech Lake Accord eventually died in 1990, and most scholars agree Quebec’s invocation of the notwithstanding clause played a key role (Monahan, Reference Monahan1991; Russell, Reference Russell2004).
There is an irony in the role the notwithstanding clause played in the death of Meech: a constitutional instrument designed to prevent centralization helped doom an explicitly decentralizing set of constitutional amendments. The Accord’s promised provincial role in the selection of Supreme Court judges was designed to reduce the centralizing tendencies of the Charter, but the Charter’s only existing check against centralizing powers helped put a dagger into Meech. To this day, the selection process for Supreme Court judges remains entirely at the behest of the federal government, and any provincial consultation has been ad hoc.Footnote 2
Bill 178 did not just help kill the Meech Lake Accord, however. It also helped make the notwithstanding clause politically unpalatable outside Quebec for almost three decades. Between 1989–2017, the notwithstanding clause was invoked in four new statutes in Quebec and only once outside Quebec (Alberta’s 2000 Marriage Amendment Law).Footnote 3 As Snow (Reference Snow2009) notes, many scholars (Manfredi, Reference Manfredi2001: 194; Russell, Reference Russell2007: 67) implicitly adopted a historical-institutionalist “path dependent” explanation for why the notwithstanding clause fell into relative disuse outside Quebec after 1989. The clause had become so politically unpopular that one scholar suggested it had become a “Paper Tiger,” available in theory but not practice, while another suggested its disuse may have led it to reach the status of constitutional “desuetude” (Leeson, Reference Leeson2000; Albert, Reference Albert and Macfarlane2018). The way Quebec’s Bill 178 delegitimized the clause was arguably compounded by Alberta’s failed 1998 attempt to use section 33 to prohibit victims of sterilization laws from suing for additional compensation, a bill the government withdrew in the face of public uproar. Christopher Manfredi (Reference Manfredi, James, Abelson and Lusztig2002: 163) has used the strategic model of judicial behaviour to argue that these events, combined with the centralizing tendency in judicial review, weakened the notwithstanding clause as a constraint on judicial power and incentivized Canadian courts to impose more aggressive Charter remedies.
In 2017, the notwithstanding clause was suddenly back. After a Saskatchewan Court of Queen’s Bench decision held that funding non-Catholic students to attend Catholic schools violated the Charter, the Saskatchewan government responded by introducing legislation invoking the notwithstanding clause, and the bill ultimately passed into law in 2018. In total, eight provincial bills invoking the notwithstanding clause have been introduced since 2017, six of which—two each in Ontario, Saskatchewan and Quebec—have passed into law. Outside Quebec, more new laws have been passed invoking the notwithstanding clause in the last six years (five) than in the preceding 36 years (three). This resurgence suggests that something has shifted in terms of the strategic constraints provincial legislatures face in their willingness to use the notwithstanding clause. We discuss this below.
Conservative Provincial Rights and the Charter
In this section, we argue that shifting partisan dynamics are one factor explaining the resurgence of the notwithstanding clause. We show how provincial conservatives have increasingly used the notwithstanding clause to achieve partisan ends amidst wider jurisdictional conflicts with the Liberal federal government. In this context, the notwithstanding clause has been reframed as an assertion of provincial rights against federal and provincial partisan rivals.
The context surrounding the notwithstanding clause has changed since 2018: if the post-1988 disuse of the notwithstanding clause could be explained by path dependence, that path has since shifted. One reason is that the new path began with a relatively uncontroversial use of the notwithstanding clause. The Saskatchewan Good Spirit decision was complicated, and the Charter right at stake, freedom of religion, was taken by some commentators to be better protected by offering non-denominational students access to public funding to attend constitutionally protected Catholic schools (Baron and Sigalet, Reference Baron and Sigalet2017; Newman, Reference Newman, Sigalet, Webber and Dixon2019: 228–9). Saskatchewan’s use of the notwithstanding clause drew criticism from some legal scholars (Roach, Reference Roach2017; Sirota, Reference Sirota2017), but the government’s reasoning was vindicated at its provincial court of appeal (Good Spirit School Division No. 204 v. Christ the Teacher Roman Catholic Separate School Division 2017). Yet other invocations of the notwithstanding clause that followed Saskatchewan’s new path were controversial, especially Ontario’s 2018 Efficient Local Government Act (which sought to reduce the size of Toronto’s City Council but was ultimately withdrawn after a judicial decision was stayed); Quebec’s 2019 An Act respecting the laicity of the state (which bans government-affiliated employees, including teachers, from wearing religious symbols and was renewed in 2024); and Saskatchewan’s 2023 Parents’ Bill of Rights (which requires parental consent for children under 16 to change their name and gender pronouns in school).
Indeed, the provincial revival of the notwithstanding clause is arguably at odds with both the popularity of the Charter of Rights and Freedoms and the historical unpopularity of the clause itself. The Charter has always been popular with all Canadians since its inception, and the public generally favours courts over legislatures when it comes to questions of rights (Goodyear-Grant et al., Reference Goodyear-Grant, Matthews and Hiebert2013; Angus Reid Institute, 2015; Bricker, Reference Bricker2018; Breton, Reference Breton2024). Furthermore, survey data showed significant opposition to the clause in Ontario in 2018 (Bricker, Reference Bricker2018; McGregor et al., Reference McGregor, Anderson and Pruysers2021), while Nicolaides and Snow (Reference Nicolaides and Snow2021) have shown that media stories from 2017–2018 tended to be far more negative than positive about the clause. On the other hand, more Canadians approved than disapproved of the most recent invocation of the clause in Saskatchewan’s 2023 Parents’ Bill of Rights (Leger, 2023). The public opinion environment concerning the notwithstanding clause has clearly shifted in recent years, with support depending on region, partisanship and the policy issue. The mixed evidence about the popularity of the clause suggests that any shifts in public opinion about the clause itself are likely endogenous to other variables.
These post-2018 invocations have one thing in common: they have all been introduced by conservative governments for partisan ends, including the Saskatchewan Party, the Coalition Avenir Québec (CAQ) and the Progressive Conservatives in New Brunswick and Ontario. Some of these uses have been for ideologically conservative policies. For example, legislators from the governing Saskatchewan Party defended Saskatchewan’s 2023 Parents’ Bill of Rights for conservative reasons emphasizing parental rights. However, Minister of Justice Bronwyn Eyre added a federalism dimension by asking “why is one Canadian province accused of rewriting the rules when it avails itself of the same powers that Quebec does?” and arguing that using section 33 protects “legislative sovereignty” in “the long running tension and balance between legislative and judicial and federal and provincial powers” (Eyre, Reference Eyre2023: 4107).
However, the bills invoking the notwithstanding clause are not all in line with ideological conservatism. For example, New Brunswick introduced a 2019 bill on mandatory vaccination for children in public schools, and Ontario’s 2022 law strengthened campaign finance restrictions that had been passed by the previous Liberal government but which were widely acknowledged to be in the Conservative government’s partisan interest. Even in Saskatchewan’s Parents’ Bill of Rights, Saskatchewan Party Minister Eyre framed the NDP’s opposition to the policy as counter to their own history by pointing to the clause’s bipartisan origins and its support from former NDP Premier Alan Blakeney (4106). Overall, the bills have not been uniformly ideological, apart from the theme of democratically asserting provincial jurisdiction. The fact that section 33 is not only invoked by legislatures controlled by parties focused on provincial rights like the Saskatchewan Party and the CAQ, but also by traditionally less regionally assertive provincial Progressive Conservatives, suggests that conservative ideology is shifting in favour of legislative assertions of provincial rights across the country.Footnote 4
Relatedly, there are signs of shifting partisan attitudes about the clause among voters. Crandall and Lawlor (Reference Crandall and Lawlor2022) have demonstrated a growing partisan divide in support for the courts, with conservative Canadians less supportive. Regional ideology remains relevant, as federal partisans of the separatist (and left-leaning) Bloc Québécois, rather than the Conservatives, were most supportive of the notwithstanding clause at the national level (Lawlor and Crandall, Reference Lawlor and Crandall2023: 15). However, conservative partisanship was also a factor in a survey experiment from McGregor et al. (Reference McGregor, Anderson and Pruysers2021), who found that approval for uses of section 33 was higher among partisan supporters of Ontario’s Progressive Conservatives than supporters of opposition parties and non-partisans (McGregor et al., Reference McGregor, Anderson and Pruysers2021).
Shifting voter attitudes appear to be driven by political elites. But what is driving conservative elites to reframe section 33? We argue that provincial conservatives may be embracing the notwithstanding clause as a result of increased partisan disagreement over Charter rights and agitation for provincial rights against Justin Trudeau’s Liberal federal government (2015–2025). In the past, there was a regional divide amongst Canadian conservative leaders outside Quebec when it came to the notwithstanding clause: Ontario Premier Bill Davis was publicly critical of the clause, for example, whereas Alberta Premier Ralph Klein was more willing to support using the clause. By contrast, today’s provincial conservatives from East to West are more willing to use every constitutional tool available to them—including the notwithstanding clause—amidst a new strategic environment involving wider jurisdictional conflicts with a Liberal federal government. Conservative provincial leaders are ideologically reframing the clause in a positive light, as it becomes a useful tool for achieving policy goals opposed by their provincial and federal partisan rivals. This reframing may be made easier by the fact that provincial premiers can legitimate the clause by pointing to its historical origins as an instrument for resisting centralism (as the Saskatchewan Party did in 2023).
We are not claiming that the Supreme Court (or courts in general) are causally responsible for the rising commitment of provincial conservative parties to provincial rights. The rise of conservative provincial rights partly stems from modern ideological congruence between political conservativism and federalism, which is clearly present in both Canada and the United States (Glaser et al., Reference Glaser, Berry and Schildkraut2023). Yet there also is also a long history of progressive demands for decentralization in Canada and the United States, and the link between modern Canadian conservatism and federalism is tied to historical partisan conflicts and regional politics (Vipond, Reference Vipond1991; Beienburg, Reference Beienburg2024). This link has been reinforced by wider jurisdictional conflicts between provinces controlled by conservative parties and the federal Liberal government. In 2015, seven provinces were governed by Liberals; by 2025, it was only two (New Brunswick and Newfoundland and Labrador). By 2018, half of the provinces were controlled by conservative parties, with a majority of seven by 2019 (now six after the 2024 defeat of the Progressive Conservatives in New Brunswick).
In recent years, jurisdictional clashes about matters such as the federally mandated minimum carbon tax, federal bans on single-use plastics, clean energy regulations and emissions caps have all been framed by provincial conservatives as partisan struggles against overreaching centralization (Hartery and Sigalet, Reference Hartery and Sigalet2024). Conservative governments in Alberta and Saskatchewan in particular have enacted legislative assertions of provincial sovereignty while aggressively pursuing litigation strategies against centralizing federal laws. In 2022, Alberta’s United Conservative Party (UCP)-controlled legislature also enacted an “anti-commandeering” statute, the Alberta Sovereignty Within A United Canada Act (Sovereignty Act), including a clause enabling the legislature to declare that federal laws violate the Charter (Hartery and Sigalet, Reference Hartery and Sigalet2024). Likewise, Saskatchewan enacted the 2023 Saskatchewan First Act, which formally asserts autonomy over non-renewable natural resources. Even past periods of partisan conflict between federal Liberals and provincial conservatives, such as Peter Lougheed’s famous conflicts with Pierre Trudeau over natural resources in 1980, did not feature such legislative exercises of extra-judicial constitutional interpretation. Today, these partisan federalism conflicts extend beyond the West and Quebec to provinces traditionally less aggressive in protecting provincial autonomy like Ontario and New Brunswick. Compared with previous eras of jurisdictional conflict, the coalescence of current federal/provincial differences over ideology, partisanship and centralization has produced a qualitatively different strategic intergovernmental environment.
The partisan framing of these jurisdictional conflicts makes it easier for provincial conservatives to perceive Charter challenges to provincial laws as another area of creeping centralization. The Supreme Court has played a strategically mixed role in federalism cases involving jurisdictional disputes. On the one hand, in the 2021 References re Greenhouse Gas Pollution Pricing Act, the Supreme Court of Canada delivered a major blow to the provinces by upholding the federal regulatory scheme for greenhouse gases, a law imposing a minimum “backstop” tax on carbon emissions on all provinces. On the other hand, the Court has subsequently limited the centralizing effects of this decision by holding the federal Impact Assessment Act to be an unconstitutional infringement of provincial jurisdiction (Reference re: Impact Assessment Act 2023).
The provinces are keen to use courts to contest centralization (including via the reference procedure; see Puddister, Reference Puddister2019), but the enactment of Alberta’s Sovereignty Act and the Saskatchewan First Act help show that they are also co-ordinately seeking to advertise their own constitutional judgements about incursions into their sovereignty. However, unlike in federalism cases, the provinces have an extra tool in the Charter context: the notwithstanding clause. Because the clause allows the provinces to disagree with a Charter decision they perceive as imposing partisan national standards, the clause has become ideologically repackaged as a constitutional tool for achieving conservative ends in what is just one front of a wider set of partisan centralization conflicts.
The federal Liberals have arguably encouraged this partisan framing of the notwithstanding clause, as it fits in well with the party’s brand as the “Charter Party” champion of pan-Canadian civil liberties (see Sigalet and Baron, Reference Sigalet and Baron2016). When asked about Ontario’s 2022 invocation of the notwithstanding clause, federal Liberal Minister of Labour Seamus O’Regan responded by calling it an “affront to democracy” (Patel, Reference Patel2022). Prime Minister Justin Trudeau directly criticized Ontario’s and Quebec’s invocations of section 33 as “an attack on people’s fundamental rights,” as the “trivialization [banaliser] of suspensions of rights,” and suggested that his government might send a reference question to the Supreme Court to curb such uses (Aiello, Reference Aiello2022; Bellavance, Reference Bellavance2023). This prompted Ontario’s Conservative Premier Doug Ford to challenge Trudeau to open talks about constitutional amendment with premiers “if he wants to go down that road” (Aiello, Reference Aiello2022). Quebec Premier François Legault likewise condemned Trudeau’s words as “a frontal attack” on the “collective rights” of Quebec (Amador, Reference Amador2023). This framing helps turn what are formal disagreements between the courts and provincial legislatures about Charter rights into an extension of other ideologically charged federalism disputes. Such partisan framing makes it easier to reshape and overcome popular skepticism about laws impacting judicial power by politicizing the rights issue as a question of partisan and federalism-based conflict, rather than simply legislative/judicial conflict.
Rising partisan jurisdictional conflicts are not the only factor explaining the resurgence of section 33. There have been past periods of partisan jurisdictional conflicts in post-Charter history that have not featured spikes in section 33 usage. Below, we review evidence for a second interacting factor: the Supreme Court is increasingly striking down a far higher proportion of provincial statutes for violating the Charter.
Rising Invalidation Rates at the Supreme Court of Canada
To test whether Charter invalidation rates have changed, we draw from an original dataset of every Supreme Court of Canada case from 1982 to 2020 in which the Court was asked to review the constitutionality of statutes enacted by the federal Parliament and provincial legislatures for compliance with the Charter. The dataset, which runs from the Supreme Court’s first such case in 1984 until the end of the Supreme Court’s October 2020 term, is part of a larger project involving statutory invalidations in Canada and the United States. It includes a total of 301 Supreme Court of Canada cases (205 federal, 96 provincial), including reference cases. Each case was coded for 16 (provincial) or 18 (federal) variables, including the type of decision, the effect, the rights area, the enacting legislature and statutory responses to the decision. For the purposes of this article, the most important variable analyzed was whether all or part of a challenged law was upheld or invalidated. This was coded as a binary, with “invalidated” including laws that were struck down and/or judicially amended in whole or in part. Our dataset did not assess whether the Court was correct to invalidate laws, as such an exercise is inherently normative.
Between 1984 and 2020, there was not a major difference in the total proportion of invalidated statutes, with federal statutes invalidated in 33 per cent of cases compared with 35 per cent for provincial statutes. Yet these numbers belie considerable variation over time. As Table 2 demonstrates, the Supreme Court of Canada has been invalidating both federal and provincial statutes at a much higher rate in recent years. The rate of invalidation of federal statutes stayed at a relatively stable rate between 28 and 31 per cent for the first 27 years of Supreme Court jurisprudence (1984–2010); however, from 2011 to 2020, it rose to 51 per cent, with the Supreme Court invalidating 18/35 cases in that period.
Table 2 Supreme Court Invalidation Rate by Decade

The rise in the provincial invalidation rate since the 1990s has been even more dramatic. The rate doubled from 21 per cent (6/29 cases) from 1991 to 2000 to 42 per cent (10/24 cases) from 2001 to 2010. From there, it rose even higher from 2011 to 2020, to a remarkable 62 per cent, or 8/13 cases. While the actual number of federal and provincial statutes invalidated by the Supreme Court of Canada has not increased considerably (owing in part to a general decline in the Supreme Court’s caseload),Footnote 5 the proportion of invalidations has grown steadily. If the Supreme Court grants leave to a challenge (or reference) to a statute, there is an increasing likelihood that the law will be struck down, especially at the provincial level. Figure 1 displays the same data as a five-year moving average, showing a dramatic spike for both levels of government that started around 2010.

Figure 1. Five-Year Moving Average of Invalidated Cases, 1984–2020.
It is important to note that the Supreme Court’s rising invalidation rates have occurred during a period in which the Supreme Court is granting leave to appeal in fewer cases in general, some of which could have been cases regarding provincial laws the Court might have otherwise upheld. However, our data show that the Court has increasingly invalidated the provincial laws it does review. Even if the Court shows deference to the provinces by not reviewing laws it might otherwise uphold, its decision to invalidate an increasing proportion of the laws it does hear reduces the positive value of Charter review for provincial politicians. Although the absolute number of invalidations has been relatively stable, the fact that provinces are losing a higher rate of Charter challenges can send the signal that the courts are a risky institutional venue. It is also possible that vertical stare decisis entails that lower Supreme Court upholding rates will allow lower courts to invalidate higher proportions of provincial laws, although this claim should be tested in future work with lower court data.
Overall, our data reveals a strategic environment where the cost of Charter centralization has been rising for the provinces. This has corresponded to a post-2015 strategic environment in which a federal Liberal party has clashed with a conservative provincial rights movement, which has increased the willingness of provincial politicians to look for constitutional tools to fight centralization.
Analysis: The Regime Politics of Charter Centralization
The data help us understand the strategic environment that provinces inhabit vis-à-vis courts. This environment is complex because Canadian courts can serve provincial interests in at least two ways: first, courts can protect provincial constitutional jurisdiction in federalism disputes between Parliament and provincial legislatures; second, judicial decisions upholding provincial laws for compliance with the Charter can have value for provincial political elites seeking to vindicate policies that divide their party coalition or cross-pressure government and opposition parties (Whittington, Reference Whittington2005: 589-93).
The value of constitutional judicial review can complicate how provincial political actors calculate how to respond to adverse judicial decisions, because attempts at “court curbing”—“a legislative proposal to restrict, remove, or otherwise limit judicial power” (Clark, Reference Clark2009: 978)—could affect the ability of courts to protect provincial jurisdiction in federalism cases. There is a centralizing cost for provinces when they lose a Charter case that can incentivize court curbing. The court-curbing capabilities of Canadian provincial legislatures are also more limited than the federal Parliament or the US Congress in some respects, because the provinces control neither the appointment nor term length of any superior court judges. Like the federal prime minister and Parliament, provincial premiers and legislatures do have de facto powers to not enforce judicial decisions (as Alberta arguably did in the wake of Mahé. v. Alberta Reference Alberta1990); unlike American states, they have the de jure power to override judicial review under many sections of the Charter, using the notwithstanding clause. The notwithstanding clause represents a form of court curbing because it limits judicial power to review and invalidate statutes invoking section 33 under the Charter (see Lawlor and Crandall, Reference Lawlor and Crandall2023). Compared with other court-curbing instruments such as “court packing” or non-enforcement, however, the notwithstanding clause does not directly attack the judiciary as an institution.
In light of these strategic considerations, we would expect that in order for provinces to risk devaluing constitutional judicial review by using the notwithstanding clause, the costs of Charter review would need to increase. This is confirmed by our data. Yet even after Saskatchewan invoked section 33 in 2018, provinces have not used the notwithstanding clause in response to invalidating decisions by the Supreme Court (indeed, the notwithstanding clause has not been used in response to a Supreme Court decision since 1988). Rather, provinces have tended to use the notwithstanding clause in response to trial court decisions, or to pre-emptively invoke the clause when they know their legislation risks invalidation under existing precedent or future judicial decisions. The rising probability of Charter invalidations shown by our data suggests that provinces may be responding to (or pre-empting) trial court invalidations with statutes invoking the notwithstanding clause, because they are increasingly less confident of reversing any invalidation on appeal.
Our analysis does not include a normative assessment of whether the courts were correct to invalidate laws on the basis of existing jurisprudence. However, from an empirical standpoint, our data show that invalidations as a percentage of Supreme Court cases are increasing: the 2011–2020 period was the first since 1982 in which the Supreme Court upheld fewer provincial and federal laws than it invalidated, with the Court’s invalidation rate of federal and provincial statutes at its highest level since the entrenchment of the Charter. Yet there remain key differences between the federal and provincial strategic environments. Unlike provinces, the federal government retains the tool of judicial appointments for the Supreme Court and all superior courts, by which it can theoretically influence judicial decision making over the long term without the need for statutes invoking the notwithstanding clause. Federal politics also features bicameralism and broader political coalitions from different regions of the country. This may increase the value of judicial review to federal politicians as a means to overcome coalitional fractures or entrenched interests to reform the status quo (via courts invalidating older laws) or to affirm controversial laws (via courts upholding new laws). Finally, federal interests can be served by judicial review that invalidates provincial laws for violating federal jurisdiction or national standards of rights. By contrast, there is not necessarily any policy decentralization when the Supreme Court invalidates federal laws for violating national standards of rights.
Discussion and Conclusion
Using within-case process tracing and drawing from an original dataset of Supreme Court decisions, we have argued that the post-2018 revival of the notwithstanding clause has occurred within a shifting strategic environment where the benefits of judicial review under the Charter have diminished for provincial governments. This has occurred due to the Supreme Court’s increased invalidation rates of provincial laws in cases subject to the notwithstanding clause, which has transpired alongside the rise of a conservative provincial rights movement driven by wider jurisdictional conflicts with a Liberal federal government.
This argument lends empirical weight to the “centralization thesis,” whereby the Charter has led to a structural loss of policy autonomy for the provinces (see Cairns, Reference Cairns1992; Morton, Reference Morton1995). It also demonstrates a broader theoretical argument in support of the centralization thesis: that, from an institutional standpoint, a constitutional bill of rights applied to all levels of government and interpreted by a federally appointed judiciary will tend to be centralizing. When the Supreme Court strikes down a provincial law for violating the Charter, it is applying national standards to an area of provincial jurisdiction. There is no corollary application of provincial standards to a federal law struck down for violating the constitution—it is merely national standards applied by a different political institution. This is why the rising invalidation rate of provincial laws portends greater centralization when the rising federal invalidation rate does not entail decentralization. Theoretically, if the Supreme Court struck down federal laws at a much higher rate than provincial laws in salient areas, particularly with respect to criminal laws with a healthcare dimension (see Kelly, Reference Kelly2001: 350–1), the Charter could be an instrument for decentralization. But even in this uncommon scenario, the Court would be making jurisdictional room for provinces without actively binding the federal government to provincial rights standards. This basic centralization cost of Charter review helps explain why rising invalidation rates incentivize provinces to use section 33.
To be clear, our argument seeks to explain the political behaviour of provincial elites, not judicial behaviour at the Supreme Court of Canada. While ideology could play a role in driving judicial behaviour (particularly in leaves to appeal), such a determination is beyond the scope of this paper. Our data confirm that the Supreme Court of Canada is invalidating a higher proportion of laws for violating the Charter, but here we offer no explanation for why such increased invalidation is occurring—a question that ought to be investigated in future research. Instead, our argument is that these increasing invalidations of provincial laws have changed the strategic considerations facing provinces, which have increased their propensity to use the notwithstanding clause. A rising proportion of invalidations of provincial laws, combined with wider partisan federalism conflicts, have contributed to a changing strategic environment for the provinces.
In such an environment, the notwithstanding clause is a more attractive court-curbing mechanism than politically attacking courts or threatening non-enforcement of judicial decisions. The notwithstanding clause does not directly attack judges or restructure the judiciary: it simply enacts laws notwithstanding judicial review for renewable five-year periods. This is related to the wider regime politics game provinces are playing. Provinces need to resist Charter centralization in ways that do not devalue judicial review more generally, such as in federalism conflicts, so the costs of Charter centralization must rise significantly beyond any benefits before provinces will risk using the clause. Rising invalidation rates have increased these costs in ways that interact with partisan federalism conflicts. Wider jurisdictional conflicts have helped incentivize provinces to use section 33 because the clause allows them to resist judicial intrusions on their jurisdiction, while publicly attacking provincial partisan rivals and the federal government rather than the courts. Conservative premiers have generally avoided directly attacking courts and instead defended their invocations of section 33 against provincial partisan rivals and Prime Minister Justin Trudeau and his cabinet. Rising invalidations incentivize uses of section 33 to protect provincial jurisdiction; partisan federalism conflicts lower the political costs.
How provincial conservative leaders respond to a potential future Conservative federal government, particularly one supportive of the notwithstanding clause, will be telling. Conservative Prime Ministers have shifted their view towards the Charter and judicial power over time; Prime Minister Brian Mulroney (1984–1993) was among the strongest critics of the notwithstanding clause; Stephen Harper (2006–2015), by contrast, was much more positive about the clause, although he did not come close in invoking it. As Macfarlane (Reference Macfarlane2018: 2) notes, the Harper era led to a breakdown of the bipartisan commitment to the “pro-Charter regime” that had previously existed at the federal level—a breakdown which, as we show, is now taking place even more dramatically at the provincial level. Current federal Conservative leader Pierre Poilievre has maintained Harper’s skepticism towards judicial power by promising to use the notwithstanding clause for criminal justice laws; he has also criticized Prime Minister Trudeau for intruding into policy debates regarding provincial pronoun policies, an area where Saskatchewan has invoked the notwithstanding clause (Canadian Press, 2024; Thompson, Reference Thompson2024). The ability to potentially draw partisan support for provincial uses of the clause from federal Conservative allies in opposition to federal Liberals has likely helped incentivize provincial conservatives to use section 33. Given more substantial federal court-curbing powers, a federal Conservative government could diminish incentives for provincial conservatives to make use of section 33 by constraining judicial power for shared partisan ends.
Our data does present limitations, most notably insofar as our dataset is case-based, which entails selection problems (Gardner and Thrower, Reference Gardner and Thrower2023: 140). Future scholarship should explore judicial invalidation rates using statute-based data, although such data will need to account for the problem of lower baselines of provincial review given the existence of ten provincial legislatures. Notwithstanding such limitations, this article makes several contributions to the political science and legal scholarship on constitutional bills of rights. Much of the comparative scholarship on bills of rights and judicial review discusses Canada’s notwithstanding clause as an instrument of “weak-form” or “non-final” or “dialogical” judicial review (Tushnet, Reference Tushnet2008; Gardbaum, Reference Gardbaum2013; Hickey, Reference Hickey2019; Dixon, Reference Dixon2023). Such comparative work tends to focus on how the notwithstanding clause renders judicial review formally non-final while failing to discuss its role as an instrument for opposing centralization. We show the strategic logic explaining how the “finality” of judicial review is more likely to be contested, and therefore less stable, at the subnational level because judicial review has a centralizing tendency.
This article also contributes to scholarship showing how court-curbing threats of non-compliance and legislative response can constrain judicial behaviour (Gardner and Thrower, Reference Gardner and Thrower2023; Carrubba et al., Reference Carrubba, Gabel and Hankla2008; Clark, Reference Clark2009; Harvey and Friedman, Reference Harvey and Friedman2006; Vanberg, Reference Vanberg2005). Canada’s notwithstanding clause is increasingly used by provincial conservative governments in part because the provinces have failed to constrain judicial review of rights questions, even as they seek to use courts to contest ideologically hostile federal incursions into their jurisdiction. This also offers a kind of negative imaging of federal constraints on courts: the continued federal disuse of the clause suggests federal power over judicial appointments—and the control of federal political branches by broad political coalitions that support rights as symbols of national identity—appear to have been sufficient to guide judicial rights review to serve federal interests. While our case study is limited to the Canadian context, it suggests that rights-based judicial review in other federal systems might have similar centralizing constraints on substate power.
This article could also prove instructive for normative debates about the notwithstanding clause. In the “Core of the Case Against Judicial Review,” Jeremy Waldron mentions the notwithstanding clause as formally rendering Canadian rights review “intermediate” in strength while de facto counting it as “a form of strong judicial review… affected only slightly by the formal availability of the override” (2016: 200-1). Conversely, proponents of judicial review like David Watkins and Scott Lemieux take the relative disuse of the notwithstanding clause (prior to 2018) as evidence that judicial review is “more normatively legitimate and more consistent with the general preferences of elected legislators” than critics like Waldron imply (Watkins and Lemieux, Reference Watkins and Lemieux2015: 314). From both perspectives, it is generally taken for granted that the main question about the notwithstanding clause is related to whether its disuse affects the democratic credentials of judicial review. However, in our view, the revival of the notwithstanding clause underlines how normative theory must grapple with the tension between federalism as a model of rights protection and the centralizing potential of national bills of rights.
Proponents of federalism have long argued in favour of its value as a bulwark against minority or majority domination, arguing that federalism works as a counter-majoritarian instrument making it more difficult for national majorities to dominate national minorities (Abizadeh, Reference Abizadeh2021), while also preventing political minorities from undermining the democratic rights of local majorities (Waldron, Reference Waldron2016). Judicial review is also often celebrated as a counter-majoritarian instrument for protecting minorities (Watkins and Lemieux, Reference Watkins and Lemieux2015), but the “regime politics” approach to understanding judicial power shows that judicial review is more likely to serve the political interests of powerful political regimes (see Macfarlane, Reference Macfarlane2018). In this article, we suggest that judicial power is primarily a function of federal (that is, national) regime power.
If the federal government has more court-curbing tools available to it than the provinces (such as appointment powers), then it will have less need for section 33 to constrain judicial policy making regarding the Charter. While this is not the only factor explaining why the federal Parliament has yet to use the notwithstanding clause, our analysis suggests that judicial review can provide greater value for national governments in federal regimes as an instrument of centralization. We also show how partisan federalism conflicts help animate constraints on such centralization by enabling the subnational use of court-curbing mechanisms. Insofar as the judicial review of bills of rights undermines the counter-majoritarian promise of federalism, it could be perceived as a threat to provincial rights. In that case, those concerned with provincial rights will be grateful to have the notwithstanding clause as a constraint on centralization.
Finally, while today’s notwithstanding clause proponents tend to be conservatives, we caution that this is by no means destined to remain true. Although the provincial rights movement today involves provincial conservatives struggling with federal progressives, early Canadian and American constitutional history involved provincial and state progressives resisting federal conservatives. Insofar as different configurations of partisan conflict help animate uses of the notwithstanding clause, it may thereby protect the ability to settle rights disagreements without loading the ideological dice.
Acknowledgements
This article is indebted to the excellent research assistance of Neelesh Thakur (who helped construct the original dataset), Depti Manhas and Dylan Clarke. Many thanks to the participants at the 2023 UBC Constitutional Workshop for comments and conversations.
Competing interests
The authors declare none.