Stuart Banner is a legal historian who has written books on the history of baseball’s antitrust exemption, the struggle to control airspace and how American Indians lost their land. On Wednesday, Banner achieved a new distinction: He won his first U.S. Supreme Court argument.

Banner, a law professor at the University of California, Los Angeles, and a former clerk to Justice Sandra Day O’Connor, won in the high court in Nelson v. Colorado. The justices, in a 7-1 opinion by Justice Ruth Bader Ginsburg, held that Colorado’s Exoneration Act—the exclusive scheme for refunds of costs, fees and restitution paid by exonerated defendants—violated the Fourteenth Amendment’s guarantee of due process.