Abstract The past few years have witnessed a proliferation of universal jurisdiction proceedings in Europe, many of which concern asylum seekers suspected of committing international crimes in Syria and the wider region. Alongside the known practical challenges of such trials, these trials also raise a range of normative questions regarding inter alia the scope of universal jurisdiction and the applicable legal standards in such proceedings. This article unpacks several such questions through the lens of a recent Dutch case in which a former refugee, who was granted asylum in The Netherlands and later obtained Dutch citizenship, was tried and convicted by a local court in The Hague of war crimes committed in Ethiopia four decades ago. The judges used an amalgam of Dutch and (customary) international criminal law to convict the accused. They defined the charged war crimes in strict conformity with the standards established in international legislation and jurisprudence, relied exclusively on Dutch law to define one of the applied modes of criminal liability (co-perpetration), and synthesized Dutch and international law to define the other (command responsibility). To what extent does the notion of universal jurisdiction accommodate such choices of law, and how is the use of domestic criminal law on modes of liability in such proceedings compatible with the principle of legality?