 Prakken (1997) book provides an extensive treatment of the contributions of techniques from nonmonotonic logic to the formal modeling of legal reasoning. See also Prakken and Sartor (1996, 1998), Hage et al. (1993), Hage (1997), Lodder (1999), and Bench-Capon et al. (2004, 2009). Kevin Ashley’s HYPO system (Ashley 1990) employs defeasible reasoning in the study of case-based reasoning in the law.