Citation Analysis of Canadian Case Law

  • Thom Neale Sunlight Foundation, CanLII
Keywords: network analysis

Abstract

This study uses simple statistical and functional analysis in conjunction with network analysis algorithms to examine the network of Canadian caselaw using data supplied by the Canadian Legal Information Institute (CanLII). The analysis reveals that indegree centrality and PageRank scores of caselaw within the network are effective predictors of the frequency with which those cases will be viewed on CanLII's website. Further, statistical and functional analysis of network rankings of each case over time suggest that cases typically cease to be cited in 3 to 15 years, depending on the jurisdiction, with the exception of Supreme Court of Canada decisions, which persist for 50 years. The study concludes that roughly 19% of Canada Supreme Court cases remain important despite the passage of time, whereas in all other jurisdiction, less than 3% of cases continue to be cited regularly over time.

 

Author Biography

Thom Neale, Sunlight Foundation, CanLII
Thom Neale is a software developer located in Boston,Massachusetts. He is an attorney licensed in New York and Massachusetts, but prefers to spend his time writing code to transform, analyze, and visualize legal information. He currently works for the nonpartisan, nonprofit Sunlight Foundation on its Open States project, an effort to aggregate and standardize legislation for all fifty states.

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Published
2013-12-18
Section
Data organization and legal informatics