Two hundred years after Marbury v. Madison, constitutional review has spread to all parts of the world. Yet it remains an eminently contentious practice, which has spawned a vast scholarly literature. Surprisingly, though, little has been done to make the normative debate conversant with comparative and empirical research on judicial behaviour and institutions. The present paper seeks to evaluate two distinct approaches to the justification of constitutional review which it takes to be implicit in the normative scholarship: (1) The Principal-Agent Model, which essentially views constitutional review as a means to enforce the choices of the constitutional framers over recalcitrant legislative majorities. And (2) the Trustee Model, which cast...