The OBR and the Politics of Forecasting Brexit Effects

Abstract

AbstractThis chapter focuses on the practical and technical difficulties that the Office for Budget Responsibility faced when forecasting the economic effects of Britain’s decision to leave the European Union. It outlines the market contestation surrounding different conceptions of free trade, and how these fed disagreements over interpretation of Brexit’s likely economic effects. The backdrop to Brexit forecasts was politically contested understandings of the relationship between Europe and the British model of capitalism. The event’s unprecedented nature, the uncertainty surrounding the Brexit process, and the difficulty disaggregating its economic impact from other factors all made the OBR’s forecasting work especially challenging. The acrimonious and often fallacious terms of the Brexit debate also posed difficulties for a technocratic economic governance institution seeking to retain its apolitical, independent credentials while developing its economic narrative. The OBR sought to manage Brexit uncertainties through conservative assumptions and judgement informed by modelling by other expert economic bodies. Nevertheless, Brexit forecasting entailed the OBR taking a normative stance not only on the economic value of Britain’s membership of the Single European Market but also on competing conceptions of the nature, operation, and feasibility of ‘free trade’. Demonstrating how the OBR’s judgements proved particularly contentious for advocates of a post-Brexit Global Britain, the chapter explores how radical uncertainty created the conditions for alternative, specious economic expertise to gain plausibility. It emphasizes the hidden normative foundations on which all economic forecasting is premised, and which always threaten to puncture the OBR’s epistemic authority by illuminating its technical limits.