Optimal legal standards in negligence-based liability rules

Making use of the neoclassical production-function approach, four negligence-based liability rules are analysed in a noncooperative game,viz: The negligence rule, strict liability with contributory negligence, negligence with contributory negligence and strict liability with dual contributory negligence. The most remarkable result is that with the last two rules in force the socially optimal can also be attained in some situations in which only one of the two necessary legal standards of negligence (for the victim and for the injurer) is set at the socially optimal level.