An odd mix of U.S. Supreme Court justices Jan. 15 condoned steep prison terms for pickpockets, shoplifters, and purse snatchers.

The decision in the hotly contested case over the oft-litigated Armed Career Criminal Act was a victory for the federal government in the first divided opinion of a so-far-sleepy term.

Justice Stephen G. Breyer joined Justice Clarence Thomas’ majority opinion, as did Justices Samuel A. Alito Jr., Neil M. Gorsuch, and Brett M. Kavanaugh.

Meanwhile, Chief Justice John G. Roberts Jr. joined Justice Sonia Sotomayor’s heated dissent—as did Justices Ruth Bader Ginsburg and Elena Kagan.

As far as Breyer...