Our Data

The Evidence Behind the Book

Our research explores a fundamental question in Canadian politics: Why do most parliamentarians remain so loyal to their political parties?

We’re examining the institutional forces and political culture that create strong expectations for party discipline and teamwork. This includes a closer look at the psychology of group loyalty, the influence of workplace dynamics in political settings, and how partisan norms shape behaviour across all levels of experience—from first-time candidates and rookie MPs to long-serving party veterans.

To shed light on these dynamics, we’ve compiled a comprehensive dataset of Canadian parliamentarians who left their party caucus between 1980 and 2021 but continued serving as Independents or members of another caucus. Our dataset captures 349 instances involving 333 individuals, some of whom exited more than once. For each case, we documented key details including name, year of departure and/or defection, years in office, province, gender, age, and the parties involved.

We enriched this dataset by reviewing over 3,000 news stories, producing briefing notes that contextualize the controversial circumstances around each departure. This work offers a rare, in-depth look at party switching and disloyalty in Canadian federal and provincial politics.

We are providing access to our full party defectors database and briefing notes through the University of Alberta Borealis-Dataverse.

Through this project, we aim to better understand how loyalty is forged, enforced, and sometimes broken in Canada’s parliamentary system.