The Impact of Ideology on Judicial Behaviour on the High Court of Australia

It is widely accepted outside of Australia that the voting behaviour of justices on apex courts is affected by the justice’s political preferences (or ideology). In numerous countries—including the United States, Canada, the UK, France, Germany, Brazil, Israel, and Taiwan, amongst others—political scientists and legal scholars accept that justices of apex courts are important players in the political system. Yet, in Australia there persists a popular narrative that justices of the High Court of Australia are uniquely apolitical, with ideology having little or no effect on judicial decision making. In this paper we ask the foundational question of whether the ideology of the justices of the High Court of Australia impacts their voting behaviour. We develop a proxy measure for ideology by undertaking a content analysis of all newspaper articles written about each justice sitting on the High Court between 1995 and 2019 in the 6-month period prior to their swearing in. We then examine the veracity and reliability of the scores against a new hand-coded dataset that measures the ideological direction of each vote the justices in every non-unanimous decisions of the High Court of Australia from 1995-2019. Overall, we find substantial evidence of ideological voting, with ideology highly correlated with votes across multiple policy areas, net of other factors. Our findings call into question the assumption that the High Court is an apolitical institution and suggest that both Australian politics scholars and scholars of Australian law and courts should be cognisant of ideological polarisation on the High Court of Australia, particularly as Australia moves closer to a bill of rights.

About the presenter:

Professor Zoe Robinson is a Professor of Political Science at the School of Politics and International Relations, Australian National University. Her research interests are at the intersection of law and politics, and focuses on law and courts, judicial behaviour, and constitutional law and politics. She was previously a professor of law in the United States, earning her PhD and JD at University of Chicago, as well as her LLB and BA from the ANU.