[MUSIC] Guido Calabresi, in possibly the most important tort book every written, The Costs of Accidents, argued that the optimal tort liability regime is one that minimizes the sum of the cost of accidents, and the sum of avoiding accidents including the administrative costs of the tort system. Calabresi concluded that such a regime will sometimes call for assigning tort liability to the least cost avoider. The least cost avoider sometimes is also called the cheapest cost avoider. It's party who is best able to minimize these costs. So imagine there's a factory that is polluting and causing damage to nearby neighbors. If it's cheaper for the factory to install a scrubber or move than it is for the neighbors to move or acclimatize to the noxious fumes, then the factory is the least cost avoider. This concept can be applied across a host of areas in the law where a potentially avoidable harm has occurred. A retailer drafts an offer mistakenly leaving off a zero from the price of an iPad. When that happens courts might ask, are there contexts where the offeree is the least cost avoider, instead of the offerror who placed the mistaken ad? Or imagine that a factory uses an employment agency to hire a new worker, only to find six months later that the worker had undocumented residency status. Again, the court applying the least cost avoider concept might ask, who was better placed to avoid this mistake, the agency or the employer? What is the relationship between least cost avoider analysis and the claims of the coast theorem? Or can you think of other circumstances where the concept could be used? PS, the pedant in me wants to point out that when there are only two parties involved, it would be more appropriate to refer to one as the lesser cost avoider. This is because least is a superlative adjective which should only be used when comparing three or more things, but no one says that. [MUSIC]