Since its inception in 1957, Malaysia's Federal Court (FC) has often been embroiled in high-profile decisions that have dramatically shaped the rule of law and constitutional practice in Malaysia. Recent political change has renewed hope that the FC can reassert its early role as an independent and impartial arbiter of political conflict. This paper investigates determinants of the FC's behaviour since 1960. It draws on a unique data set of 102 major political cases and socio-biographic profiles of the 73 judges who voted in these cases. After describing patterns of court decisions across time and judges, we test specifically for the impact on their decisions of the 1988 judicial crisis, length of time on the bench, the terms of successive prime ministers, and judges' personal attributes, such as religion and ethnicity. Ethnicity, appointment after 1988, and the appointing prime minister proved to be closely associated with the direction of voting. We then position the results in the context of Malaysia's evolving constitutional democracy and discuss their implications for students of comparative judicial politics.