From his Blue Mass. Group site (blue to reflect his Democratic colors):
The LA Times reports today that Supreme Court nominee John Roberts gave substantial behind-the-scenes assistance, pro bono, to the activists who asked the Supreme Court to overturn Colorado's infamous "Amendment 2," which prohibited municipalities in Colorado from adopting any gay-friendly ordinances or policies. . . .
What to make of this? Is Roberts a clandestine agent of the dreaded "homosexual agenda"? Is he, in fact, secretly gay? (Perhaps that would explain his son's controversial pastel clothing?)
Maybe. But more likely, he was doing his job. A partner at Roberts's firm was working with the plaintiffs in Romer; the partner asked for Roberts's help (Roberts was, after all, the firm's best Supreme Court lawyer), and Roberts agreed. And having agreed, he gave it his all, reviewing briefs, preparing the lawyers for oral argument, and generally being "terrifically helpful." That is exactly what lawyers are supposed to do.
This is, in other words, an excellent illustration of how difficult it is to discern a lawyer's views from his professional activities. . . .
I will say this, though. It is of course always open to a lawyer to decline to participate in a case because for whatever reason the lawyer cannot in good conscience represent the client's interests in that case. The fact that Roberts agreed to participate in Romer at least suggests that he was not viscerally, fundamentally opposed to the pro-gay rights result that the plaintiffs sought in that case. . . .
More at David's site.