In this paper we discuss the disparate treatment of perceptual (\u27\u27fact\u27\u27) witnesses and expert witnesses in the legal system. We highlight the distinction between the perceptual act of witnessing and the act of testifying, and argue that although there might be good reasons to regulate payments to fact witnesses, the customary prohibition on paying them for their services is not justified by reference to economic theory. We propose considering a court mediated system for compensating fact witnesses so as to encourage witnessing of legally important events.We construct a simple model of witness incentives, and simulate the effects of several possible payment mechanisms. Although it is possible that any system that offers a financ...