Winning a 2003 landmark U.S. Supreme Court case expanded a gay lawyer's Supreme Court practice, he says, and looking back, it's his favorite case.

Because Paul M. Smith was the editor-in-chief of the Yale Law Journal, clerked for then-U.S. Supreme Court Justice Lewis F. Powell Jr. and handled various Supreme Court cases—including for paying clients—many thought that it made sense for the Washington, D.C., lawyer to argue Lawrence v. Texas, which led to a 2003 landmark opinion that struck down state laws criminalizing sexual conduct between consenting adults of the same gender.