Wojciech Sadurski (University of Sydney – Faculty of Law) has posted Searching for Illicit Motives: Constitutional Theory of Freedom of Speech, Equal Protection, and Separation of State and Religion on SSRN. Here is the abstract:
The general idea that only such exercises of public power are legitimate which are based on properly “public” reasons, and that reasons which are inadmissible taint an authoritative decision with illegitimacy, can be translated into a constitutional doctrine under which improper legislative motives contaminate a law with unconstitutionality, even if we may approve of the effects of such laws. But is such a “translation” legitimate? First, I consider the arguments made by two leading American constitutional lawyers and theorists: Laurence Tribe and Rick Pildes, and conclude that they provide support to the idea of motivation-based scrutiny of constitutionality. I then apply, in the subsequent three sections of this working paper, the idea of unconstitutional motivations as a test of (un)constitutionality to three areas of constitutional law: freedom of speech, equal protection, and separation of state and religion. The aim is to show that a constellation of various doctrines specific to these three can often be best understood if we presuppose a meta-doctrine of (un)constitutional motivations, which resonates with the philosophical ideal of public reason.
Highly recommended.
For some thoughts on this topic, see Public Legal Reason.