DAMAGE

Sharing a damage that has been caused by several individuals is a difficult problem that courts often face. Even if there exist basic principles and rules to apportion damages among them (like for instance in the third Restatement of Torts promulgated in May 1999 for the United-States), legal scholars are still looking for a systematic method. Many examples of such litigation come to mind: a car driver hurts a pedestrian and breaks his or her leg. Then, the victim is taken to a hospital to be looked after but, because of the fault of the surgeon, he or she completely loses the use of his or her leg and gets amputated. Apportionment rule is needed to correctly share the damage paid by each tortfeasors. Such litigations occur as soon as two or more individuals have jointly caused damages and it is easy to think about the different fields of law concerned by this issue: environmental law and nuisance, accident law, medical malpractices, products liability, victim contributions, securities law, antitrust etc. The aim of the paper is to reconsider the issue of apportionment among multiple tortfeasors to expose some economic principles which could be applied by the judiciary in order to rationally share the damages due by each tortfeasor. But contrary to many models in law and economics, we do not use a non-cooperative game approach. In the following, damage is modeled as a cooperative game where different agents – the tortfeasors – jointly create an indivisible economic loss, the damage. The DAMAGE project aims at showing how the cooperative approach may bring useful insights into legal questions. The main issue we address in this project is the following. We use cooperative game approach as a model to evaluate the causal role of each tortfeasor. Our aim is to build a set of structured games which fit with the main cases of multiple causation (successive injury, victim’s fault, joint damage etc.) and to solve these games with usual solution concepts used in cooperative game theory. Then we will study the consequences of such apportion rules on the incentives followed by the tortfeasors. This main issue leads to two others issues. The first one is to know whether cooperative game approach is consistent with contemporary counterfactual theories of causation. The second one is to study whether the French jurisdictions practices (mainly civil courts) are enlightened by our approach. We will proceed to an empirical study by building an original data set on the main French courts decisions on this topic. And this date base will finally be open to legal scholars, judges and lawyers.