Politics in the courtroom
Shamena Anwar, Patrick Bayer, and Randi Hjalmarsson use the random assignment of politically appointed lay judges at Gothenburg District Court to estimate causal effects on verdicts. The local PDF is the 2015 working-paper version; the peer-reviewed article appeared in 2019.
Adding a Sweden Democrat lay judge increased the conviction share by about 17 percentage points for defendants with Arabic-sounding names. Adding a Left Party lay judge increased the conviction share by about 14 percentage points in cases with a female victim. The study also found peer effects on more centrist lay judges.
The design is unusually strong because assignment was random, but it concerns one district court and a historical period. It establishes that political composition affected outcomes in that setting; it does not measure every Swedish court or current party effect.
The study grounds Swedish lay judges and political influence and the institutional analysis in Rättssäkerhet in Swedish criminal cases.