Nash Implementable Liability Rules for Judgement-Proof Injurers

I provide a complete characterization of Nash implementable allocations of spending in prevention by judgement-proof injurers. This characterization is used to identify the optimal rule that allows for the maximum total spending in prevention. The optimal rule amounts to apply the negligence rule to the "deep-pocket" (or the "victim"), that is the injurer who responds the most to monetary incentives under the strict liability rule, and the strict liability rule to everybody else.