The Effect of Judicial Independence on Courts: Evidence from the American States

This paper provides new evidence on the relationship between judicial independence and the quality of state courts. The paper examines two state-level factors that affect judicial independence: i) state judicial retention policies and ii) stability of the state constitution. The paper shows that these two factors are largely determined by a combination of statelevel initial conditions and lagged state-level political variables. Using initial conditions and lagged political variables as instruments, the paper finds that increasing judicial independence by changing judicial retention policy away from partisan elections would increase the quality of state courts by roughly one and a half standard deviations. Similarly, increasing independence by decreasing the state constitution amendment rate from the 75th percentile to the 25th percentile would increase the quality of courts by roughly three quarters of a standard deviation.