This article sheds new light on the role of national courts in the preliminary ruling procedure and European integration by examining: (1) whether national courts allow the Court of Justice of the European Union (CJEU) to decide politically sensitive cases and (2) whether national courts frame the cases by expressing support for an integration-friendly interpretation of EU law or by voicing an opinion in defence of the challenged national law. This study shows that the single most common court behaviour is to support legal integration by referring politically sensitive cases and expressing support for EU law. However, by examining the two choices together, this article also uncovers previously untheorised patterns of behaviour. These findings show that the national courts’ behaviour is not limited to either supporting or resisting integration. Instead, it is suggested that national courts may regularly contribute to striking a balance between EU integration and member state autonomy.