Current fourth amendment law is a confusing mess that has become more confusing as the result of the United State's Supreme Court's misapplication of the balancing approach based on the criterion of reasonableness. However, a cost-benefit approach could produce coherence, making fourth amendment law both internally consistent and socially optimal by thoughtfully balancing the relevant interests. Optimality would consist of minimizing the sum of several costs. These costs would include the cost of obtaining evidence, costs associated with criminals who are not incapacitated, costs of the loss of privacy of individuals, and the costs of errors and administration. This approach would not be applicable in all situations, but it would provide a method for more focused, coherent, and intellectually honest debate and legal reforms. Footnotes