Did liberalising English and Welsh bar hours cause traffic accidents?

Legal bar closing times in England and Wales have historically been early and uniform. Recent legislation liberalised closing times with the object of reducing social problems thought associated with drinking to "beat the clock." Indeed, we show that one consequence of this liberalization was a decrease in traffic accidents. This decrease is concentrated heavily among younger drivers. Moreover, we provide evidence that the effect was most pronounced in the hours of the week directly affected by the liberalization; late nights and early mornings on weekends. This evidence survives a series of robustness checks and suggests at least one socially positive consequence of expanding bar hours.