Thirty years ago, a young William M. Acker Jr. successfully argued a racial bias case at the U.S. Supreme Court on behalf of black railroad workers. Now a senior federal judge in Alabama, he returned to the high court recently, not as an advocate but as an alleged tax scofflaw. Victory may be more elusive the second time around.

For now at least, Judge Acker, who sits on the district court in Birmingham, and his benchmate, Judge U.W. Clemon, are on the side of legal right: Two lower federal courts have found the Jefferson County occupational tax-which both judges have balked at paying for nearly a decade-to be unconstitutional. Whether the U.S. Supreme Court will agree is harder to say, particularly after oral arguments March 29 that gave no clear indication of where the justices were heading.