Interest in Indian law is growing as the economic clout and political influence of the nation's 562 federally recognized tribes have expanded. Arizona State's Indian Legal Program allows students who are pursuing their J.D.'s to simultaneously earn certificates in Indian law. They study the differences between the legal systems of tribes and that of the U.S. government, and many go on to represent the interests of tribes, Indian clients, or the federal government. Wenona T. Singel, an assistant professor of law at Michigan State University, says about 20 law schools nationwide report having Indian-law programs, while other experts say the number of full-fledged programs is about 12. Among the other law schools active in Indian law are those at Harvard University, Lewis and Clark College, and the Universities of Colorado, New Mexico, Washington, and Wisconsin.