Research note: A comparison of free vote patterns in Westminster-style parliaments

The research note examines levels of intra-party cohesion during free voting on abortion, euthanasia and same-sex civil partnerships and marriage in the lower houses of four Westminster-style parliaments: Australia, Britain, Canada and New Zealand. In free vote circumstances, to what extent do political parties in these 'most similar' parliaments remain cohesive? Do political parties with similar ideological commitments exhibit similar levels of cohesiveness across the parliaments? The main finding of the article is that, although the level of cohesion within political parties varies depending upon the issue being considered, across the four parliaments, political parties with similar ideological commitments display broadly similar patterns of intra-party cohesion during free vote circumstances. Whilst 'centre-left' parties were the most cohesive on abortion and civil unions, but divided on euthanasia, 'centre-right' parties were consistently split on all three issues.