Justices Ginsburg and Gorsuch Switch Sides

A truly interesting and unusual Supreme Court line-up.

Today the Supreme Court decided four cases, one of which featured a particularly unusual -- indeed unprecedented -- line up of justices.

In Mont v. United States, the Court decided, 5-4, that if a criminal defendant's pretrial detention is later credited as time served for a new conviction, that detention counts as "imprison[ment] in connection with a conviction" and thus tolls the supervised-release term under federal law, even if the court must make the tolling calculation after learning whether the time will be credited.

One reason the Mont decision may be of interest beyond those with an interest in federal criminal sentencing is the 5-4 line up it produced: Justice Thomas wrote the majority opinion, joined by the Chief Justice, and Justices Alito, Kavanaugh, and Ginsburg. Justice Sotomayor wrote the dissenting opinion, joined by Justices Breyer, Kagan, and Gorsuch.

This line up is interested on multiple levels. At first the decision appears to have produced a traditional 5-4, conservative-liberal split, until one notices that Justice Ginsburg joined with the conservatives and Justice Gorsuch joined the liberals. The resulting division is thus neither one we expect to see ideologically, nor is it readily explained on the basis of other common jurisprudential divisions, such as the formalist-pragmatist split we've often seen in other criminal justice contexts. Further, while we've seen Justice Gorsuch cross over to vote with the liberal justices in other cases, we have not seen this in a case in which one of the more liberal justices also "switched sides."