Which court hears a judicial review application in Ontario and how do I start one?

In Ontario, judicial review applications are generally heard by the Divisional Court, under the framework set out in the Judicial Review Procedure Act, rather than by a single judge sitting alone the way many other civil matters are heard. Starting one generally involves filing a formal application setting out the decision being challenged, the tribunal or decision-maker involved, and the grounds for review, such as a lack of fairness in the process, a decision outside the decision-maker's legal authority, or a conclusion that was unreasonable given the evidence and legal framework involved.

Judicial review is generally treated as a remedy of last resort where other adequate options exist, meaning a court may decline to hear a judicial review application if there's a more appropriate internal review or appeal route within the tribunal's own process that hasn't been used first. Courts also generally expect judicial review applications to be brought without undue delay after the decision being challenged, rather than sitting on the issue for an extended period. Because judicial review involves its own specialized procedure, distinct from an ordinary civil lawsuit, getting advice on both whether it's the right remedy and how to properly frame the application is genuinely valuable before starting one.