Another common case law research task is to find decisions on a given topic.
This type of task may feel daunting to a novice researcher because of the huge amount of Canadian case law that is available online.
This page describes a few strategies and finding tools that can make locating decisions on a topic easier:
The best place to start searching for cases by topic is secondary sources, also known as commentary.
Resources like legal encyclopedias, textbooks, treatises, annotations, and journal articles point you towards leading cases in a particular area of law or on a specific topic.
►See Secondary Sources for more information.
A major challenge with searching case law is that keywords often retrieve many irrelevant cases in areas of the law that are not applicable to your research.
One way to mitigate this challenge is by using topical classification, which refers to any system where cases (or other documents) have been assigned a label that refers to their subject matter.
Depending on the system, topical classification can be very high level (e.g. Family Law) or extremely granular (e.g. Family Law—Divorce—Grounds—Living apart—Time period).
Use the dropdowns below to learn how to find subject classification within CanLII, Westlaw, and Lexis.
Keyword searching can be a challenge in case law databases because judges may not always use the same language to describe your legal issue.
There are two main types of search:
Some research platforms allow you to use only one type of search. Westlaw and Lexis both default to natural language search, but provide the option of conducting a Boolean search as well.
No matter where you are searching, it is important to understand how the system is processing your search so that you can improve your ability to retrieve relevant results.
Tips for a successful keyword search:
1. Spend time developing good keywords. The success of a search depends on the words you use. See "Extracting Keywords" in Christa Bracci & Erica Friesen, Legal Research Online (eCampus Ontario Open Library, 2024) for more information.
2. Use pre-filters wherever possible to limit your caselaw universe. One common problem researchers have is using generic keywords that retrieve thousands of results in a database. To avoid this, use pre-filters to narrow field of focus before conducting your search by either selecting a sub-database (e.g. Ontario court decisions) or by using an Advanced Search form.
3. Use search syntax to be precise with your search. Boolean operators are words and symbols that can be used in conjunction with keywords to make your search much more precise. The following tutorial provides an introduction to Boolean operators.
Use the dropdowns below to learn where to find the documentation on Westlaw, Lexis, and CanLII. If you are using another database, check its documentation to determine which Boolean operators are accepted and how to trigger them.
The following mini tutorial provides an overview of some basic types of Boolean connectors. Note that search connectors vary by database. The examples provided in this tutorial are based on connectors in CanLII, Westlaw, and Lexis.
Westlaw has several topical case law databases.
Note: you may run into an "out of plan" message if you try to view resources other than case law in these databases.
