Lawyers think they know what makes a successful appeal but there aren't any numbers. What's the chance that a client's appeal will succeed? That's hard to answer but an analysis of thousands of Supreme Court decisions shows that there are factors that make cases more or less likely to result in a win for the appellant.

The odds calculator that you see below allow you to see what the approximate chance of success is for a person contemplating an appeal to the Supreme Court of Canada. Read more at the bottom of this page.

Choose a Province and Area of Law

Statistical Odds of a Win for Appellant

Change the province or area of law above to see the chance of winning below.

Statistical Measure: Based on Area of Law Based on Province/Court Based on Area of Law + Province
Probability of Win:
Percentage of all appeals filed that result in a win: 5.2%

These odds are based on an analysis of 4390 civil Supreme Court decisions decided between 2005 and 2014.

Cases Used to Generate Results Above

Area of Law Area of Law + Province

More Information

How does it work? I've written a program to download and parse every Supreme Court of Canada decision since around 2005. I used the program to separate out the decisions by originating court (e.g. Ontario Court of Appeal), area of law (e.g. Administrative Law), and determine (using the docket data for each case) whether the appeal resulted in a win for the appellant or not.

If you'd like to access the raw data you can just download the JSON files that this page loads. If you don't understand that sentence, just send me an email, I'd be happy to chat further and explain:

This builds on earlier work that I did based on 2006-2014 data. You can find it here:

Numbers are only shown when at least twenty cases have been decided for that category. This cutoff is rather arbitrary but reflects that only about 5% of cases result in wins. If the cutoff was lower there would be very misleading results.

Here's some research I did on the Ontario Court of Appeal using similar methods: “Court of Appeal Statistics: Costs”, “Ontario's 50 Top Appellate Lawyers” & “ONCA Decision Word Frequency”.

Yes, I do know there's a difference between odds and probability. This page doesn't make the distinction and everything is expressed in probabilities.