Roger Alford at Opinio Juris makes an important point that most of us, me included, haven't really focused on in the debate over the use of foreign law in US courts - its use by lower courts and state courts. He notes that the Missouri Supreme Court appealed to foreign law in its opinion in Roper v Simmons, flagrantly ignoring then-controlling US Supreme Court precedent. I've noted in earlier posts that foreign law, unless checked by a newly constituted Supreme Court (and the fact that Roberts and Alito are both opposed does not really change the situation all that much, given that Kennedy, Stevens, Breyer, Souter, and Ginsburg are all on board), will become much more a feature in the lower courts than we now realize, through the press of litigation. But Roger Alford's post notes that it is already present more than I, at least, had really thought about. Here.