Instant-runoff voting is used in whole or in part to elect the leaders of the three largest federal political parties in Canada: the Liberal Party of Canada, the Conservative Party of Canada, and the New Democratic Party, albeit the New Democratic Party uses a mixture of IRV and exhaustive voting, allowing each member to choose one format or the other for their vote (as was used in their 2017 leadership election). In 2013, members of the Liberal Party of Canada elected Justin Trudeau as party leader through IRV in a national leadership election. The Conservative Party used IRV (where each of the party's 338 riding associations are weighted equally, regardless of how many members voted in each riding) to elect Erin O'Toole as party leader in 2020, Andrew Scheer in 2017, and Stephen Harper in 2004.