This article analyses to what extent the mechanism of the coalition conflict model of executivelegislative relations can account for the extent and policy direction of parliamentary control over domestic transposition, focusing on EU migration law. Our empirical approach is based on an in-depth cross-country comparison of the transposition of the Returns Directive in Austria, Germany, France, and the Netherlands. We find that in all four countries the legislatures left their marks on the final laws, and the policy direction of amendments was largely in line with the predictions of the model. Yet, the policy adjustments were not always triggered by coalition partners correcting ministerial drift, but also by factions within the ministerial party, and by opposition parties.