‘If you can't beat me, join me!’ How the Commission pushed and pulled member states into legislating defence procurement

The smooth adoption of the European Union (EU) defence procurement directive in 2009 is puzzling, because member states had fiercely opposed legislation for the sensitive defence-industrial sector before. We argue that the Commission's strategic usage of judicial politics changed member states' opportunity structure and, by this, transformed a blocking majority of member states into legislative consensus. As it drew on new case law, the Commission pushed member states and threatened to leave the regulation of defence procurement uncontrolled to the European Court of Justice (ECJ). In parallel, it promised member states to restore legal certainty and political control if they would approve EU legislation on defence procurement. Following a process-tracing logic, we compare the failed Commission initiatives until 2005 with the adoption of the directive in 2009. Finally, the available evidence is checked against alternative explanations.