Politics in the Courtroom: Political Ideology and Jury Decision Making

This paper uses data from the Gothenburg District Court in Sweden and a research design that exploits the random assignment of politically appointed jurors (termed nämndemän) to make three contributions to the literature on jury decision-making: (i) an assessment of whether systematic biases exist in the Swedish nämndemän system, (ii) causal evidence on the impact of juror political party on verdicts, and (iii) an empirical examination of the role of peer effects in jury decision-making. The results reveal a number of systematic biases: convictions for young defendants and those with distinctly Arabic sounding names increase substantially when they are randomly assigned jurors from the far-right (nationalist) Swedish Democrat party, while convictions in cases with a female victim increase markedly when they are assigned jurors from the far-left (feminist) Vänster party. The results also indicate the presence of peer effects, with jurors from both the far-left and far-right parties drawing the votes of their more centrist peers towards their positions. Peer effects take the form of both sway effects, where jurors influence the opinions of their closest peers in a way that can impact trial outcomes, and dissent aversion, where jurors switch non-pivotal votes so that the decision is unanimous.