After the terrorist attacks of 11 September 2001 Ulrich Beck placed terrorism alongside other potentially catastrophic events such as global warming, nuclear disaster, and influenza as one of the ‘dimensions’ of risk society. In risk society, executive governments take ‘precautionary measures’ and parliaments pass ‘preventative laws’ allowing them to accumulate information, detain terrorism suspects, freeze funds and prohibit various groups, in order to stop catastrophic risks from eventuating. International Relations and legal scholars have used risk society theory or the ideas of Michel Foucault to criticise such excesses of the executive and parliamentary branches of government. Most studies either ignore the judiciary or argue that it stands in opposition to the other branches of governments, that it imposes checks and balances in order to uphold the rule of law and protect individual rights. The article argues that this view is naïve and does not acknowledge a long history of judicial deference to the will of the executive and parliament. Through an analysis of case law from Australia and Canada the article explores parallels between early 21st century judicial reasoning and previous periods of crisis, including the Cold War, while identifying some new ‘precautionary approach’ aspects. The judiciary defers to the executive, asserts that the executive is more accountable than it, and seeks to avoid responsibility for engaging in this ‘precautionary justice’. Furthermore, seized by the same fear of terrorism as executive governments, the judiciary shows an ability to adapt existing legal concepts to the exigencies of risk society. The article concludes that as the memory of the 9/11 attacks fades some of the most draconian preventative measures may be scaled back but the judiciary cannot be relied on to keep the executive or parliament in check.