(for example, Rubin, 1994 and 2004). Additionally, by demonstrating the difficulty of achieving the goal of efficiency, they have helped scholars to understand when the law may be efficient and when it is likely not to be. Moreover, an important component of the evolutionary models was their focus on the litigation decision as driving legal evolution. Other models of legal evolution both economic and non-economic. either leave mechanisms for evolution unspecified or assume that the preferences of judges are the driving forces The economic models were the first to focus on the motives of litigants, realizing that judges can decide only those cases that come before them. As Elliott(1985: 71)in a study of the history of evolutionary models, indicates: " Moreover, the economic school of evolution has broadened our view of the legal system to include the role of litigants, as well as judges, in making law. The literature associated with Priest and Klein(1984)on selectivity bias in case selection is a result of the focus on litigants' decisions, which has come out of the evolutionary models. ( For an analysis of theories of legal evolution from 1880-1940, which thus omits analysis of the economic theories, see Hovenkamp, 1985) Macro” Efficiency In addition to the literature that examines the efficiency of particular rules, there is a newer literature examining the overall efficiency of common law. The theoretical basis for this literature is the work of Hayek. Hayek argued that common law was created from the bottom up, rather than from the top down. The recent literature has elaborated this point to argue that common law does a better job than code law of protecting property rights from predation by the state itself.(for example, Rubin, 1994 and 2004). Additionally, by demonstrating the difficulty of achieving the goal of efficiency, they have helped scholars to understand when the law may be efficient and when it is likely not to be. Moreover, an important component of the evolutionary models was their focus on the litigation decision as driving legal evolution. Other models of legal evolution, both economic and non-economic, either leave mechanisms for evolution unspecified or assume that the preferences of judges are the driving forces. The economic models were the first to focus on the motives of litigants, realizing that judges can decide only those cases that come before them. As Elliott (1985: 71) in a study of the history of evolutionary models, indicates: “Moreover, the economic school of evolution has broadened our view of the legal system to include the role of litigants, as well as judges, in making law.” The literature associated with Priest and Klein (1984) on selectivity bias in case selection is a result of the focus on litigants' decisions, which has come out of the evolutionary models. (For an analysis of theories of legal evolution from 1880-1940, which thus omits analysis of the economic theories, see Hovenkamp, 1985). “Macro” Efficiency In addition to the literature that examines the efficiency of particular rules, there is a newer literature examining the overall efficiency of common law. The theoretical basis for this literature is the work of Hayek. Hayek argued that common law was created from the bottom up, rather than from the top down. The recent literature has elaborated this point to argue that common law does a better job than code law of protecting property rights from predation by the state itself.1 9