The Relationship Between Force Majeure Clauses and the Excuse Defenses

Many commercial contracts include force majeure clauses that excuse the parties from performing some or all of their obligations upon the occurrence of specified supervening events. The law is unclear as to the proper relationship between such clauses and the assertion of common law or statutory excuse defenses such as impossibility, impracticability, or frustration of purpose with regard to supervening events that are outside of the scope of such clauses. In particular, under what circumstances, if any, should a force majeure clause be regarded as preclusive of these excuse defenses with regard to those supervening events that the clause does not cover? In addition, should the determination that a particular supervening event is outside of the scope of a force majeure clause then be relevant for the determination of the merits of a subsequent excuse defense that is based upon that event?

The judicial authority on these questions is surprisingly sparse, and I offer some recommendations as to how the courts should address these issues.