Since Canada is a common law jurisdiction, we rely on the legal principle of stare decisis ("let the decision stand") whereby a lower court must follow the legal principles established by a higher-level court in the same jurisdiction.
To ascertain whether a decision is still authoritative, noting up is always necessary. This is a two part process described below.
It is essential to note up every case you are using in your research to both ensure that it is still "good law" and help strengthen your legal research. It would be unwise to base an argument on a decision that has later been overruled or reversed by a higher court, or has a long record of negative judicial treatment.
The first step is to verify the complete history of the case to determine whether it has been overruled or reversed by a higher court since it was decided. Decisions from related proceedings are also often included.
Determining the subsequent judicial treatment of a case means determining whether the decision has been mentioned, followed, distinguished, or discussed by judges in later cases.
There may be hundreds or thousands of cases that mention your target case. Use any available filters and keywords to target the most authoritative cases in your jurisdiction, as well as any cases that discuss your case in detail instead of just as a passing mention.
You can accomplish both steps in noting up using a tool called a citator. All three of the major legal research services in Canada have a version of this tool.
First, navigate to the case that you want to note up. Then, use the drop downs below to learn how to find the citator tool in CanLII, Westlaw, and Lexis.
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