Recent instances of U.S. judges — most recently, the Supreme Court's moderate liberal wing, plus moderate conservatives Justices O'Connor and Kennedy — using international law in interpreting the U.S. Constitution has led many people to be concerned. I at first wasn't much troubled.
Then, though, I expressed some worry, when I saw an argument (by a prominent liberal U.S. international law scholar) that "If some constitutional norms are more appropriately set at the international level, that should justify a treaty power that, in some cases, overcomes even the Bill of Rights." This scholar endorsed such a result, under which (for instance) international norms supporting the suppression of allegedly bigoted speech could be used to trump First Amendment rules; but I find that a very troubling consequence. And I echoed this most recently as to the cartoon affair, given the calls by a U.N. official to investigate the publication of the cartoons as potentially criminally punishable.
It turns out, though, that there has indeed been a case in which the Supreme Court was asked to uphold a restriction on speech that offends supposed international law norms — a content-based restriction on political speech in a traditional public forum, the sort of restriction that is usually treated as most constitutionally suspect. In Boos v. Barry, a local ordinance banned (among other things) "display[ing] any . . . placard . . . designed . . . to . . . bring into public odium any foreign government . . . or . . . political, social, or economic acts, views, or purposes of any foreign government" within 500 feet of that country's embassy. The ordinance was challenged by anti-Communist picketers who wanted to protest in front of the Soviet and Nicaraguan embassies.
The government, and some judges, defended the ordinance on the grounds that it was necessary to comply with international norms. International law, the argument went, banned certain kinds of speech that insults foreign ambassadors. The First Amendment must be interpreted in light of this international law norm, so that otherwise constitutionally protected speech could be suppressed because of international law. The Supreme Court ultimately rejected this argument, though not without dissent.
Here are the questions:
(1) Which controversial court of appeals judge wrote the lower court opinion that upheld the restriction on speech that insults foreign ambassadors, on the grounds that "the first amendment" "must be accommodated" with "the United States' . . . obligations under the law of nations"?
(2) Which Supreme Court Justice wrote the opinion that endorsed this view?
(3) Which Supreme Court Justice wrote the opinion that disagreed, stressing that "no agreement with a foreign nation can confer power on the [Government] . . . which is free from the restraints of the Constitution," and suggesting that "the fact that an interest is recognized in international law does not automatically render that interest 'compelling' for purposes of First Amendment analysis" (though ultimately not reaching the issue because the Justice concluded that the international law interest could be adequately served without this speech restriction)?
(4) How did the other Supreme Court Justices vote on the matter?
(1) Judge Robert Bork wrote the lower court opinion, which held that otherwise constitutionally protected speech could be restricted in the name of international law norms protecting foreign ambassadors from insult.
(2 & 4) Chief Justice Rehnquist wrote the dissenting opinion, which was joined by Justice White (who is mostly thought of as a moderate conservative) and by Justice Blackmun (who by then was something of a moderate liberal).
(3 & 4) Justice O'Connor wrote the majority opinion on this issue, which was joined by Justices Brennan, Marshall, Stevens, and Scalia. Justice Kennedy, who was on the Court by the time Boos was handed down, but not when it was argued, didn't participate in the decision (as is the norm when a Justice isn't on the Court when a case was argued).
The Supreme Court opinion is available here.
The moral of the story is that there isn't anything inherently liberal vs. conservative in the debate about using international law principles in constitutional interpretation. It may be a mostly liberal vs. conservative (or liberal plus moderate conservative vs. more hard-core conservative) debate today, but it hasn't necessarily been so in the past and needn't be so in the future.