Brief excursion into law-blogging here, following the morning Supreme Court hearing of the ridiculous challenge against Obamacare. Good summary, as usual, at SCOTUSblog.
The only reason the Court granted the appeal was because at least four justices thought they at least might want to overturn the Affordable Care Act. Four is enough to get a case heard, and you need to five to win. As SCOTUSblog notes, Scalia, Alito, and Thomas are almost certain votes to destroy health care for millions of people, while Kennedy asked questions critical of both sides (I'd guess he's leaning in favor of nonidiocy, he takes his federalism seriously).
The normally inquisitive Roberts wasn't inquisitive. Judges other than Thomas like to ask questions. If they've pretty much decided their view already, they still like to ask questions partly based on the self-delusion that they'd change their minds if given a good enough response, and partly to start jousting and convincing their fellow judges. If they haven't decided because they have unanswered questions, then they also tend to want to ask their questions.
One possibility for Roberts' silence was that he hasn't decided and hasn't even figured what questions he'd like to ask. I think that's unlikely. More likely was that he does have a viewpoint or questions but other justices were expressing them adequately, so he saw no need to pipe up. Seems most likely that Kennedy would be his doppelganger. If Roberts is going to tick off his side yet again over Obamacare, maybe he'd prefer to see Kennedy be more visible.
I'm guessing a 6-3 ruling in favor of sanity. I could be off by two votes though.