No branch of government or social institution can claim a monopoly on constitutional interpretation. The power of judicial review, therefore, cannot be equated with judicial exclusivity. Yet not all interpretations of the constitutional text qualify as constitutional law, and it may well be that the judiciary is both exclusive and supreme within this narrower sphere. In examining this possibility, Professor Allan Ides defines "constitutional law" as including only those interpretations of the constitutional text that operate as "law" as that term is commonly used within our system of government. Consistent with that usage, to be law an interpretation of the Constitution must be authoritative, regulatory, and enforceable. After measuring legislative, executive, and judicial interpretations of the Constitution against this definition, Ides concludes that with minor exceptions only judicial interpretations qualify as law. As a consequence, although the Supreme Court may not be the sole arbiter of constitutional meaning, the Court would seem to be supreme in its exposition sf the law of the Constitution.