Article VI of the U.S. Constitution provides that “…no religious Test shall ever be required as a Qualification to any Office or public Trust under the United States.”
The confirmation wars and culture wars of the past couple of decades have led to a lot of misunderstanding of this passage. This 2006 piece by law professor Paul Horwitz is a good place to start in clearing things up.
Contrary to some imaginings, the No Religious Test clause does not require a President to take no notice of the religious views of a person seeking appointment to public office. Nor does it require a Senator to set aside any notice of whether a nominee is of any particular sect (or a religious non-believer or follower of Scientology) in voting for or against confirmation. Nor — to take an even more extreme claim — does it mean that members of the electorate somehow violate the constitution when as voters they take account of candidates’ religious views.
Instead, the clause prohibits laws that would bar persons from serving in federal office unless they pledge fealty to a religious tenet. It is linked in its placement in Article VI to the preceding Oaths Clause. (It is also the only mention of religion in the originally enacted Constitution.)
It is true, as Horwitz argues, that constitutional etiquette and a due regard for pluralism may have evolved into a strong and valuable public norm here even if they do not provide a right enforceable by courts. And overstepping this norm may provide a good reason to criticize a public figure who seems to hold a certain nominee’s religion against him or her. In a more recent post, Horwitz applies those standards to the recent controversy over Sens. Dianne Feinstein’s and Dick Durbin’s comments and finds that Feinstein’s and especially Durbin’s remarks do not come off well.
Each of us should remember that however we choose to interpret the clause, that interpretation will inevitably protect appointees of exactly that strain of religious belief or unbelief we like least.
For a somewhat contrasting view, see this Harvard Law Review student note from 2007, which argues that while the President is generally in the clear when taking an interest in nominees’ religion, Senators may not be during hearings because the nominee has been placed under oath and that (the author argues) is too close to the historic abuse, at which the clause was aimed, of requiring sworn religious oaths.