Introduction

As set out in Part One, there are three distinct types of customs: epistemic customs, coordination customs, and sanction-driven customs. Epistemic customs solve nonstrategic, informational problems, while coordination customs and sanction-driven customs solve strategic problems of two different sorts.

The Prisoner's Dilemma, when iterated and solved by a social practice, is actually a subset of the broader category of sanction-driven customs and norms. A sanction-driven custom is maintained due to the existence and casual efficacy of sanctions. Along with Prisoner's Dilemma (hereinafter alternatively PD) games, games such as iterated Chicken or Ellickson's Specialized Labor Game may also be solved – or not – depending on the ability of participants to sanction one another effectively. Nearly all applications of informal game theory to law, to date, have focused on the Prisoner's Dilemma or collective action problem. One would naturally suppose that tort law would take an interest in PD-structured customs because tort law is concerned with injuries, and many PD customs present a situation in which a person is repeatedly in a position to cause injury to others, either by failing to conform to a safe PD custom or by conforming to a dangerous PD custom.

Although PD customs, and sanction-driven customs more generally, are indeed of great interest, it will be demonstrated that epistemic customs and coordination customs may be important sources of injuries as well, and so are equally of interest to tort law.