The case centers on whether the Canadian courts should consider the UK Supreme Court’s landmark 2019 decision in *R (Miller) v. Prime Minister*, known as *Miller 2*. In that case, the court ruled that then-UK Prime Minister Boris Johnson’s advice to prorogue Parliament was unlawful because it lacked a reasonable justification, particularly as it hindered Parliament’s ability to address the Brexit crisis.
In Canada, a similar legal challenge argues that Trudeau’s prorogation was motivated by partisan interests and lacked a reasonable justification, undermining parliamentary sovereignty and accountability. The lawsuit contends that the prorogation prevented Parliament from addressing key issues, such as pending US tariffs and a potential non-confidence motion that could have triggered an election.
While some legal experts, like Steven Chaplin, argue that *Miller 2* was a unique case due to the extraordinary circumstances of Brexit, the Federal Court Chief Justice has suggested that the principles outlined in the UK ruling could still be relevant in the Canadian context. The Chief Justice highlighted that the UK Supreme Court established a general test for determining the lawfulness of prorogation: a decision to prorogue is unlawful if it frustrates or prevents Parliament from performing its constitutional functions without reasonable justification.
The applicants in the Canadian case argue that Trudeau’s prorogation meets this test, as it has prevented Parliament from addressing critical issues. They claim the reasons for the prorogation are political and lack a reasonable justification.
The Federal Court has agreed to expedite the legal challenge, signaling the urgency and significance of the case. The outcome could have far-reaching implications for the balance of power between the executive and legislative branches in Canada, potentially setting a precedent for future prorogations.
At the heart of the debate is whether the principles of *Miller 2* should guide the Canadian courts in evaluating the lawfulness of Trudeau’s prorogation. While some argue that the UK ruling was a ‘one-off’ due to the Brexit context, others believe its underlying principles are universally applicable and should inform the Canadian judiciary’s decision.

Federal Court Chief Justice has emphasized the importance of considering the principles established in the *Miller 2* case when evaluating the lawfulness of Trudeau’s prorogation. The Chief Justice noted that the UK Supreme Court’s decision in *Miller 2* established a critical test for determining whether a prorogation is lawful: if the prorogation frustrates or prevents Parliament from carrying out its constitutional functions without reasonable justification, it may be deemed unlawful. The Chief Justice suggested that this test could be applicable in the Canadian context, despite arguments that the *Miller 2* decision was a unique response to the extraordinary circumstances of Brexit.
The applicants in the Canadian case have argued that Trudeau’s prorogation meets the test outlined in *Miller 2*. They claim that the three-month suspension of Parliament has prevented lawmakers from addressing critical issues, such as the imposition of US tariffs on Canadian goods and the potential triggering of a non-confidence motion. They further argue that the reasons for the prorogation are political in nature and lack a reasonable justification, thereby violating the constitutional principles of parliamentary accountability and the rule of law.
Legal experts remain divided on the applicability of *Miller 2* to the Canadian case. While some, like Steven Chaplin, argue that the UK ruling was a ‘one-off’ decision driven by the unique context of Brexit, others contend that the principles of parliamentary sovereignty and accountability outlined in *Miller 2* are universal and should guide the Canadian judiciary. The Federal Court Chief Justice’s willingness to consider the relevance of *Miller 2* suggests that the court may be open to adopting a similar approach in evaluating the lawfulness of Trudeau’s prorogation.
The Federal Court has agreed to expedite the legal challenge, recognizing the urgency and significance of the case. The outcome of the lawsuit could have far-reaching implications for the balance of power between the executive and legislative branches in Canada. If the court rules that Trudeau’s prorogation was unlawful, it could set a precedent for future cases, limiting the ability of the executive to prorogue Parliament without sufficient justification. Conversely, if the court upholds the prorogation, it could reinforce the executive’s discretion in such matters, potentially weakening parliamentary accountability.
At the heart of the debate is the question of whether the principles of *Miller 2* should guide the Canadian judiciary in evaluating the lawfulness of Trudeau’s prorogation. While some argue that the UK ruling was a unique response to the Brexit crisis, others believe that its underlying principles are universally applicable and should inform the Canadian court’s decision. The Federal Court’s ruling will not only resolve the immediate legal challenge but also shape the future of executive-legislative relations in Canada.

Conclusion
The legal challenge to Prime Minister Justin Trudeau’s prorogation of Parliament has brought significant attention to the balance of power between the executive and legislative branches in Canada. The Federal Court Chief Justice’s consideration of the UK Supreme Court’s *Miller 2* ruling highlights the potential relevance of its principles in evaluating the lawfulness of prorogation. While some argue that *Miller 2* was a unique case tied to the Brexit crisis, others believe its underlying principles of parliamentary sovereignty and accountability are universally applicable.
The outcome of this case could set a precedent for future prorogations, potentially limiting the executive’s ability to suspend Parliament without reasonable justification. The debate underscores the judiciary’s role in ensuring that executive decisions align with constitutional principles. As the Federal Court expedites the legal challenge, the ruling will not only resolve the immediate issue but also shape the future of executive-legislative relations in Canada.
FAQ
What is the lawsuit about?
The lawsuit challenges Prime Minister Justin Trudeau’s decision to prorogue Parliament for three months, arguing that it was motivated by partisan interests and lacked reasonable justification, undermining parliamentary sovereignty and accountability.
What is the significance of the *Miller 2* ruling in this case?
The *Miller 2* ruling established that prorogation is unlawful if it frustrates or prevents Parliament from performing its constitutional functions without reasonable justification. The Federal Court is considering whether this principle applies to the Canadian context.
What test did the UK Supreme Court establish for lawful prorogation?
The test is whether the prorogation frustrates or prevents Parliament from carrying out its constitutional functions without reasonable justification.
What are the implications of the Federal Court’s ruling?
If the court rules Trudeau’s prorogation unlawful, it could set a precedent limiting the executive’s ability to prorogue Parliament without justification. If upheld, it may reinforce executive discretion, potentially weakening parliamentary accountability.
Why do some legal experts argue that *Miller 2* does not apply to Canada?
Some experts, like Steven Chaplin, argue that *Miller 2* was a unique response to the extraordinary circumstances of Brexit and should not guide the Canadian judiciary.
What’s next in the legal challenge?
The Federal Court has agreed to expedite the case, recognizing its urgency and significance. A ruling is expected to provide clarity on the lawfulness of Trudeau’s prorogation and its implications for future executive actions.