Constitutional "Is" Versus Constitutional "Ought" -- A Brief Reply to Barnett and Jost:
Looking over the exchange between Randy Barnett and Timothy Jost on what it means to say something is "unconstitutional," I wonder if their disagreement is primarily semantic. We all recognize that there is often a difference between how the Supreme Court has construed the Constitution and how a particular person thinks the Constitution should be construed. The question is, what label to use for those different approaches?

  My sense is that the most common labels distinguish between what the law "is" and what the law "ought" to be. The former is what the courts say the law is, and the latter is what a particular person thinks the law should be. This appears to be the approach Professor Jost follows. Randy offers a somewhat different approach: He would say that the Constitution "is" what a proper theory of Constitutional interpretation indicates it should be — proper, that is, according to Randy — while what the Supreme Court has said it is is merely "the opinions of justices" which may be right or wrong.

  I suppose which understanding is better depends on which community you're talking to and what your goals are. Among constitutional theorists, the question of what the Supreme Court has actually said is boring; whether the Supreme Court was right is the interesting question. On the other hand, if the audience is the public, my sense is that claims by experts about what is constitutional or not are generally understood as a prediction of what the courts should do under existing law. The expert is normally consulted for expertise on existing law, not for his or her own individual theory of constitutional meaning. For example, if a reporter calls me and asks for my view on whether a particular police investigation violated the Fourth Amendment, I understand that to be asking me what a court should do based on existing law, not to apply my personal normative theory of constitutional interpretation to the facts.

  On the other hand, if you are trying to sell a constitutional vision to the public, with the aim of having your own views become more widely shared, you might speak of that vision as what the Constitution "is" on the thinking that the strong statement will have more persuasive impact. In that context, the claim of what is constitutional or unconstitutional is less a claim about the particular legislation or action under consideration and more a normative claim about how we should interpret the Constitution. Such claims can be a little misleading, as the public generally isn't told of the author's normative goals. On the other hand, those sorts of claims are common in public discourse about the Constitution.