A central requirement in the design of a legal system is the protection of law enforcers from coercion by litigants through either violence or bribes. The higher the risk of coercion, the greater the need for protection and control of law enforcers by the state. This perspective explains why, in the 12 th and 13 th centuries, the relatively more peaceful England developed trials by jury, while the less peaceful France relied on state-employed judges for both collecting evidence and making decisions. Despite considerable legal evolution, these initial design choices have persisted for centuries (largely because France remained less peaceful than England), and may explain many differences between common and civil law traditions with respect to both the structure of legal systems and the observed social and economic outcomes.
Glaeser, Edward I. and Andrei Shleifer. "Legal Origins," Quarterly Journal of Economics, 2002, v107(4,Nov), 1193-1229. citation courtesy of