Braking and Exiting: Referendum Games, European Integration and the Road to the UK's Brexit Vote.

The UK's in-out referendum on European Union membership is often attributed to an incompatibility inherent in the UK-EU relationship, or else a rising tide of Euroscepticism forcing a reckoning. We argue that the referendum should be understood as the culmination of parliamentary 'referendum games' in the preceding years, whereby backbenchers periodically applied pressure to office-seeking leaders who strategically defused this by promising public votes. These games were episodic and escalatory, coinciding with integrative European treaties which activated transient Eurosceptic backlashes. While referendum avoidance was personally rational, leaders' repeated parlays created a standalone referendum politics, ratcheting up the intensity of backbench demands based on past promises and democratic renewal. After the Lisbon Treaty, a tipping point was reached, transforming calls for a 'brake' on integration to demand for binary 'exit' vote at the next treaty moment. This accompanied the Euro-area crisis in 2011, effectively ending David Cameron's discretion to continue the game. To show this, we plot all mentions of EU-related referendums and adjacent terms in the House of Commons between 2000 and 2015. We descriptively identify five peak salience flares around EU treaty moments and then analyse 263 interventions by Members of Parliament to show how referendum pressure ratcheted up over time.