Standard Of Appellate Review In Ontario

If you’ve lost a civil case and you’re thinking about appealing, one of the first questions your lawyer will ask is: what’s the standard of review?

It might sound like legal jargon, but it directly affects your chances of winning an appeal — and it’s worth understanding before you decide to move forward.

When you appeal a court decision, the Court of Appeal doesn’t simply re-hear your entire case from scratch. Instead, it looks at what the trial judge decided and asks: was that decision wrong enough to be overturned?

The answer depends on what kind of decision is being reviewed. Different types of decisions are held to different standards — and some are much harder to overturn than others.

1. Palpable and Overriding Error (Findings of Fact)

When a trial judge makes findings of fact — for example, deciding who was more credible, or what actually happened — the Court of Appeal gives that decision significant deference.

To overturn a factual finding, you must show a palpable and overriding error. This means:

• Palpable — the error is obvious and plainly seen, not just a matter of interpretation.
• Overriding — it actually affected the outcome of the case.

This is a high bar. The Court of Appeal recognizes that the trial judge sat through the entire proceeding, heard the witnesses in person, and was in the best position to assess the evidence. Simply disagreeing with the outcome is not enough.

If the core of your appeal is that the judge got the facts wrong, you will need to identify a clear and specific error that had a material impact on the outcome of the case. 

2. Correctness (Questions of Law)

When the issue is a pure question of law — such as how a legal test should be applied, or what a statute means — the Court of Appeal applies a correctness standard.

Under this standard, the appellate court gives no deference to the trial judge. If the judge got the law wrong, the Court of Appeal will simply substitute the correct answer.

This is a more favorable standard for appellants, because you don’t need to show the error was obvious or severe — you just need to show it was wrong in law.

 Appeals based on legal errors tend to have a stronger foundation than those based purely on factual disagreements.

Many appeals involve a mix of both — for example, whether the judge correctly applied a legal test to a specific set of facts. These are called questions of mixed fact and law, and they’re the most nuanced category.

In these cases, the Court of Appeal typically applies the palpable and overriding error standard — unless the legal component of the question can be clearly separated out, in which case the correctness standard applies to that part.

Understanding the standard of review isn’t just an academic exercise. It shapes your entire appeal strategy:

• If your strongest arguments are about factual findings, you’ll need to build a very specific case around clear errors — not just a general sense that the result was unfair.
• If your strongest arguments are about how the law was applied or interpreted, you may have a more straightforward path.
• Knowing the standard early helps you and your lawyer assess whether an appeal is worth pursuing — and what it will take to succeed.

Contact us: 416.901.9984 or info@pintoshekib.ca.