Abstract. The European Union’s (EU) response to the Rule of Law (RoL) crisis has received considerable academic attention. However, the EU’s interactions with other international organisations in addressing the crisis remain understudied. This paper examines how the European Commission (‘the Commission’) has increasingly drawn on the expertise of the Venice Commission (VC), the Council of Europe’s advisory body, to substantiate its RoL monitoring and enforcement actions. Our database of Commission documents shows a growing number of references to the VC’s expertise. We conducted a qualitative content analysis of interviews with European Commission and VC officials to explore two alternative explanations for this development: capacity constraints and legitimacy reinforcement. Our findings indicate that the Commission strategically leverages the VC’s legitimacy to reinforce its own authority in countering resistance to and contestation of RoL enforcement. In doing so, the Commission seeks to meet governments’ demands, strengthen procedural standards and facilitate compliance.