The International Court of Justice ruled on May 21, 2026 that the International Labour Organization's Convention No. 87 on Freedom of Association and Protection of the Right to Organize protects the right to strike. The Court's advisory opinion, adopted by a 10-4 vote, settles a contentious dispute that has divided employer and worker representatives at the ILO for more than a decade. It may carry implications for the 158 states, including Canada, that have ratified the 1948 convention.

The ICJ, however, deliberately refrained from defining the precise content, scope, or conditions governing the exercise of the right to strike. That leaves several critical questions unanswered.

The Holding

The Court held that Convention No. 87, when interpreted "in good faith in accordance with the ordinary meaning to be given to the terms of the treaty and in light of its object and purpose," includes the right to strike.

The ICJ grounded its reasoning in the link between freedom of association and strike action. It found that the Convention's object and purpose are to protect freedom of association and the ability of workers' organizations to further and defend their interests, with striking constituting a core "activity" through which workers realize these aims. The Court also relied on interpretive materials, including related international treaties and the conduct of states party to the convention.

The opinion also emphasized limits. The ICJ noted that Convention No. 87 rights are not absolute. Article 8(1) provides that workers and employers must respect the law of the land, while Article 9(1) provides that national laws and regulations determine the extent to which the Convention's guarantees apply to the armed forces and the police.

A Decade-Long Dispute

The ILO is a tripartite United Nations agency comprising government, employer, and worker representatives. Its conventions set global labour standards that ratifying states commit to implementing through domestic law. Canada ratified Convention No. 87 in 1972.

The Convention's text does not expressly mention a right to strike. The Committee of Experts, an ILO supervisory body of independent legal experts, has long interpreted the instrument as including one. Employer representatives rejected that reading. Worker representatives endorsed it. Since 2012, the Committee on the Application of Standards, which examines state compliance with conventions, has avoided addressing the right to strike in its conclusions on Convention No. 87.

In 2023, the ILO's Governing Body voted to refer the question to the ICJ. The Court's May 21, 2026 opinion followed.

What the Opinion Leaves Open

By declining to define the right's content and scope, the Court left key questions unresolved:

• Who can strike?
• Are there limits or conditions on the right to strike — for example, political strikes, strikes during the term of a collective agreement, or solidarity strikes?
• Which authority defines these parameters?

The ILO has indicated that its Governing Body is expected to consider the matter further at its November 2026 session.

The Canadian Context

Advisory opinions are not legally binding, but they can carry significant legal weight. The opinion may influence the future work of the ILO's supervisory bodies and the discussion of Convention No. 87 in Canada and internationally.

Canadian courts already recognize the right to strike as protected by the Charter of Rights and Freedoms. In Saskatchewan Federation of Labour v Saskatchewan, the Supreme Court of Canada cited the Committee of Experts' interpretation of Convention No. 87 as persuasive authority and held that the right to strike is protected as part of freedom of association under section 2(d) of the Charter. The right is not absolute. It remains subject to justified limits under section 1.

The Ontario Court of Appeal recently confirmed that the federal and provincial governments may restrict or prohibit strike activity where the restrictions serve an important public policy purpose — such as addressing economic, health and safety, environmental, or other social concerns — and the ability to strike is replaced with a fair and balanced interest arbitration process. The Court of Appeal's reasons suggest governments should be given wide latitude to regulate and restrict the right to strike so long as fair and effective collective bargaining systems are maintained.

Strikes have also historically played a different role in Canada than in many other jurisdictions. Strikes generally unlawful in Canada — political strikes, solidarity strikes, and union recognition strikes — are common in other legal systems that informed the principles applied by the ILO Committee of Experts and the ICJ. It would be difficult, if not impossible, to import the international legal conception of strikes into the Canadian context.

Practical Consequences for Practitioners

For labour and employment counsel, the immediate takeaways are measured. The opinion does not bind Canadian courts or legislatures, and domestic jurisprudence already recognizes both the right to strike and its permissible limits. The more consequential developments will come from Geneva: how the ILO's supervisory bodies, particularly the Committee on the Application of Standards, apply and interpret the opinion going forward, and what the Governing Body decides at its November 2026 session. Employers with multinational operations should track whether supervisory bodies revive scrutiny of strike-related complaints under Convention No. 87 — a practice suspended since 2012 — and whether the opinion emboldens challenges to Canadian back-to-work legislation and essential-services restrictions in international fora. For now, the domestic framework — Charter protection subject to section 1 limits, and wide government latitude paired with fair arbitration regimes — remains controlling in Canada.

The extent to which the ICJ opinion will affect ratifying states remains to be seen, particularly in countries like Canada with robust existing jurisprudence on the right to strike and its limits.