The two “faithless elector” cases were originally consolidated to be heard together. But Justice Sonia Sotomayor late in the process discovered she knew one of the parties in the Colorado case and withdrew. That may have been a fortuitous act and provided a clean opinion in Chiafalo v. Washington—and the per curiam opinion in Colorado Department of State v. Baca gives us a hint why.

Many have focused on the substantive difference between the Washington and Colorado laws—Washington counts a faithless vote but fines faithless electors; Colorado does not count a faithless vote and replaces a faithless elector.

But there were material procedural differences, too—specifically, multiple material problems with the Colorado plaintiffs’ case in Baca. In Washington, the electors were fined and contested that in state court. Easy injury to provide (a $1000 fine), easy remedy to seek, easy cause of action to raise.

In Colorado, however, plaintiffs faced several challenges. Were their claims moot? Could they sue a state under Section 1983—or, really, could the state waive this argument when sued for damages?

At oral argument in Baca, Justice Stephen Breyer in particular with concerned about these procedural wrinkles in the Colorado case. Justice Samuel Alito and Neil Gorsuch also raised versions of such concerns.

Now, because Justice Sotomayor was recused from Baca, the principal case became Chiafalo, because all nine justices could participate. Eight justices joined Justice Elena Kagan’s opinion; Justice Clarence Thomas concurred in the judgment, which Justice Gorsuch joined in part.

Now, to the entirety of the Court’s per curiam opinion in Baca:

PER CURIAM.

The judgment of the United States Court of Appeals for the Tenth Circuit is reversed for the reasons stated in Chiafalo v. Washington, ante, p. ___.

It is so ordered.

JUSTICE SOTOMAYOR took no part in the decision of this case.

JUSTICE THOMAS concurs in the judgment for the reasons stated in his separate opinion in Chiafalo v. Washington, ante, p. ___.

I looked at this opinion a few times wondering what happened. Specifically, what happened to Justice Gorsuch? He agreed with Justice Thomas’s Tenth Amendment argument in Chiafalo. What about here? Is the Tenth Amendment no longer in play?

And then I considered another possibility—as a per curiam opinion, we don’t see the lineup of justices. Some justices may not agree with the outcome but may choose not to note their dissenting opinion. It might be the case that Justice Gorsuch (and perhaps another, like Justice Breyer) didn’t agree to reverse for the reasons stated in Chiafalo. It might be that the procedural wrinkles would have been a reason to reverse, but they opted not to publicize that here and now, saving the issue for another day.

I don’t know. I would, however, resist the urge to call Baca a “unanimous” decision of the Court. It certainly appears unanimous. But there are reasons to think that some of the procedural wrinkles would lead some members of the Court to come out differently if they couldn’t hide behind the per curiam opinion here.