Why Chief Justice Roberts Won't Side with the Liberals on Obamacare

“Some have suggested that the chief justice would vote strategically. The idea is this: He is the last justice to cast his vote during conference. If there were four votes to strike down the law, then he would provide the fifth to do the same. But if five votes had been cast for the law, Roberts would then cast a sixth vote in favor.

This would allow him to write the opinion either way, and to control how broad the opinion emerging from the court was. This is what Chief Justice William Rehnquist was suspected of doing in 1999 in United States v. Dickerson. He had been an ardent foe of Miranda, and most thought that he was a sure vote to overrule it when given a chance. But he surprised people by announcing a 7-2 decision upholding Miranda.

But there is a problem with this analogy. The task of assigning the author of an opinion falls to the most senior justice in the majority. Had Rehnquist dissented in Dickerson, the most senior justice in the majority would have been John Paul Stevens. Rehnquist had reason to fear that Stevens would assign the opinion to himself, since Stevens was the most liberal member of that court. Given some of the nuances of Dickerson, Stevens could have gutted decades of decisions chipping away at Miranda if he had written a broad enough opinion. The chief justice’s incentives to write the opinion at all costs were fairly high.

Here, the most senior justice in a majority to uphold the law — who would presumably assign himself the opinion — would be Kennedy. But Kennedy is actually fairly conservative on federalism issues. He joined the opinion of the court in United States v. Lopez and United States v. Morrison, two critical Commerce Clause cases. Even if he wanted to uphold the health care law in its entirety, it’s unlikely he would write an opinion that would set the stage for overruling those other decisions. In other words, Roberts doesn’t have the same incentive that Rehnquist might have had to vote strategically.”