What Role for Foreign Law?

The National Journal has an interesting column today about the role that international law should play in decisions of the Supreme Court. The author seems to argue that the Court's increasing awareness of the state of foreign law is not a good thing. While I can't disagree that a reliance on foreign law would be a bad thing, being aware of it and considering its merits surely has a place in Supreme Court analysis.

Legal authorities generally come in two forms, mandatory and persuasive. Mandatory authority binds lower courts in the system, andincludes decisions of the Supreme Court, which binds every lower court is required to follow. Persuasive authority refers to decisions from other courts, law review articles, and the like that do not require allegiance by the court deciding an issue. The West Virginia Supreme Court, for instance, is required to follow the US Supreme Court decisions about the Fourth Amendment. It is not required to follow the Ohio Supreme Court decisions about the Fourth Amendment, but may give them weight if they have a compelling analysis of the issue.

Unlike every other court in the land, the Supreme Court has no higher court to which is must be obedient. Every authority for the Supreme Court is persuasive. It may even overturn its own prior decisions, as it did this week in the Crawford case. So the Supreme Court is not really bound to follow anything. As that is the case, why not consult foreign law if their is something useful in it?