Populism is widely regarded in the literature as a negative and inherently punitive influence on criminal justice policy. This article challenges this view and highlights the ways in which populism can produce forms of citizen engagement in the criminal justice context that are new and progressive. These possibilities are illustrated through a close analysis of the responses to a single instance of ‘random’ fatal violence: the killing of Thomas Kelly in King’s Cross, Sydney, in 2012. This case study shows how a populist campaign powerfully realigned political allegiances to call for, and achieve, real and enduring action from the New South Wales Government in addressing alcohol-related violence.