The Evolution of Common Law

  title={The Evolution of Common Law},
  author={Nicola Gennaioli and Andrei Vasiliev Dmitry Shleifer},
  journal={Journal of Political Economy},
  pages={43 - 68}
We present a model of lawmaking by appellate courts in which judges influenced by policy preferences can distinguish precedents at some cost. We find a cost and a benefit of diversity of judicial views. Policy‐motivated judges distort the law away from efficiency, but diversity of judicial views also fosters legal evolution and increases the law’s precision. We call our central finding the Cardozo theorem: even when judges are motivated by personal agendas, legal evolution is, on average… 
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