The effect of judicial independence on courts: Evidence from the American states

This paper demonstrates that two initial conditions-having been settled by a country with a civil-law legal system (France, Spain, or Mexico) and membership in the Confederacy during the Civil War-have had lasting effects on state courts in the United States. We find that states initially settled by civil-law countries and states in the Confederacy granted less independence to their judiciary in 1970-90 and had lower-quality courts in 2001-3. Furthermore, judicial independence is strongly associated with court quality. To explain these findings, we hypothesize that civil law acted through legislator preferences regarding the balance of power between the legislature and the judiciary, with legislators in civil-law states preferring a more subordinate judiciary. The ability of civil-law legislators to act on these preferences was, however, affected by within-state political competition, which was much higher in northern states than in southern states after the Civil War.