Justice Kennedy had quite a lot to say in Virginia Office for Protection and Advocacy v. Stewart about the 11th Amendment and Ex Parte Young.

Here are some comments during the Petitioners arguments:

JUSTICE KENNEDY: But there are a number of 3 instances in the States where constitutional officers 4 have their separate autonomy, their separate 5 responsibilities. And it seems to me to follow 6 inevitably from your position that the attorney general 7 of State A could sue the governor of State A saying the 8 governor is being sued in an Ex parte Young capacity 9 because the governor is not following Federal law. I 10 think that’s just inevitable from your position, and 11 that seems to me a vast extension of Ex parte Young. 12 It’s true, I think that we’ve never said that the 13 identity of — or that the permissibility of an Ex parte 14 Young suit depends on the identity of the plaintiff; but 15 don’t we have to say that here if we are going to allow 16 the States to structure their — their own governments 17 as they choose?

…

JUSTICE KENNEDY: And the question is can one State entity enforce it against another State entity in a Federal court.

MR. GALANTER: The — there are not a lot of Federal rights that State officials have against other officials. Here, this is a right -­

JUSTICE KENNEDY: Well, but that — but under — under your theory there would be, because under Ex parte Young the whole point of it is that a — a person can allege that this fictional private individual who is really a governmental individual is violating a Federal right. That’s the whole point of it.

Kennedy had this to say during the arguments of the United States:

JUSTICE KENNEDY: Going back to your 15 exchange with Justice Breyer, I assume that you could 16 stand by your answer and say the attorney general could 17 sue the governor, because he’s not suing the governor in 18 his official capacity. He has a Federal right under Ex 19 parte Young to sue the governor as an individual. It’s 20 a fiction, we all know that. But that’s the way it 21 works and this is a Federal right. I think that’s your 22 position.

This is (I think) the first big case involving the 11th Amendment since Justice Souter left. Let’s see is Justice Sotomayor thinks along the same lines as Justice Souter, who was really a champion for the dissenting view in Alden v. Maine and Florida Seminole Tribe.