Under what conditions do politicians oppose referendums especially to decide questions of European integration? Existing literature has identified reasons why governments and political parties pledge to hold non-mandatory referendums to ratify EU treaties or determine a country's participation in the EU project, and some studies have analysed the effect of voter demand and attitudes towards EU referendums. This study examines the positions politicians themselves take towards popular participation in decision-making on the EU. The paper presents a summative content analysis of parliamentary debates in the United Kingdom between 1974 and 2010, tracing MPs' arguments against using referendums to determine the UK's participation in EU integration. Our results indicate that the range of claims made by MPs in the House of Commons against referendums on European matters has narrowed over time, although opposing arguments have continued to fall into the same set of four argumentative strategies. We find that institutional arguments, reflecting a Burkean understanding of representative democracy, consistently predominate over arguments that cite practical, political and manipulation concerns.