One quick observation on Justice Kagan’s unanimous opinion yesterday in Royal Canin v. Wullschleger, which holds—wonky federal-jurisdiction alert!—that a federal court loses jurisdiction over a case that has been removed from state court when the plaintiff amends the complaint to eliminate the federal-law claims that enabled removal.

After a very clear primer on jurisdiction, Kagan addresses “two bits of gratuitous language” from previous cases that the defendant (who is trying to salvage the federal court’s jurisdiction) “read[s] … for a good deal more than they are worth.” One of the “bits” is this passage from Justice Marshall’s majority opinion in Carnegie-Mellon v. Cohill (1988):

When the single federal-law claim in the action was eliminated at an early stage of the litigation, the District Court had a powerful reason to choose not to continue to exercise jurisdiction.

As Kagan acknowledges, “In using the word ‘choose,’ Cohill suggested that the court, though having strong cause to dismiss or remand, likewise had authority to decide the case.” But, she sensibly explains, any such suggestion in “that slender (and somewhat backhanded) dictum” was ill-considered and “gratuitous.”

As it happens, Kagan was a law clerk for Marshall when he signed his name to the Cohill opinion. It’s possible that she drafted the sloppy passage. But probably not: I’d think that she was as careful a writer back then as she is now. And as Marshall had four law clerks, the raw odds that she was the lead clerk on the case are only 25%. In any event, she has now had the opportunity to point out the problem in the passage.