"Habermas and Rawls - Disputing the Political" (Routledge, 2011), edited by James Gordon Finlayson & Fabian Freyenhagen, includes a new article by Jürgen Habermas in which he comments on John Rawls's political theory and on the other contributions in the book.
Here are some excerpts from Habermas's "Reply to My Critics" (pp. 283-304):
"How far are morality, law and politics amenable to rational justification and how do they relate to the normative content of the ethical-existential life orientations and worldviews of individuals and communities? For my part, I follow Kant in assuming that, with the concept of autonomy, the practical reason shared by all persons offers a reliable guide both for morally justifying individual actions and for the rational construction of a legitimate political constitution for society. Kant understands "autonomy" as the ability of persons to bind their will to universal norms that they give themselves in the light of reason.
Rawls takes this individualistic and egalitarian universalism into account only in his exposition of a concept of political justice, however, wheread he situates moral conceptions on the particularisic side of the plurality of "comprehensive doctrines". Nevertheless, the "priority of the right over the good", as I understand it, sets the parameters in such a way that the concept of political Justice as Fairness is composed entirely of universalized contents that can also count as "morally" justified in the Kantian sense and are not shaped by values of a particular political culture." (p. 284)
"[There is however] a problem that, in my view, besets the construction of the "overlapping consensus". The correctness of the political conception of justice is supposed, on the one hand, to be measured by whether it can be integrated into the different comprehensive doctrines as a module; on the other hand, only the "reasonable" doctrines that recognize the primacy of political values are supposed to be admitted to this test. It remains unclear which side trumps the other, the competing groups with a shared worldview who can say "no", or practical reason that prescribes in advance which voices count. In my opinion, the practical reason expressed in the citizens' public use of their reason should have the final word here, too. This admittedly calls for a philosophical justification of the universal validity of a morality of equal respect for everyone. Rawls want to sidestep this task by confining himself to a "freestanding" theory of political justice." (p. 285)
"Rawls employs the concept of "freestanding" in a more specific sense when he refers to the independence of philosophical subdisciplines from one another. (....) The reason for Rawls's intention to insulate his theoretical program from controversies in neighboring disciplines has to do with the meaning of normative political theories. He hoped that this would enable the concept of Justice as Fairness to secure broad public acceptance. I am skeptical in this regard because each of Rawls's basic conceptual distinctions - moral versus political, rational versus full autonomy, the right versus the good, true versus reasonable, reasonable versus rational, truth versus objectivity, etc. - forces him to take positions in specialist discourses that reach far beyond the boundaries of political theory. Fallibilism and continued controversies on all fronts are the price to be paid for metaphysical abstinence" (p. 290)
See my previous post on "Habermas and Rawls - Disputing the Political".