Last month, Senator Rand Paul of Kentucky proposed a federal law that would guarantee the right of ex-felons to vote in federal elections. The text of the bill, S.B. 2550, has just been released.

It's just missing one small things: a constitutional basis for the federal government to enact such a law.

A few months ago, a group of senators, led by Senator Ben Cardin, introduced S.B. 2235, the Democracy Restoration Act, that would do a similar thing.

But what, exactly, is the constitutional basis for Congress extending the right to vote to ex-felons in federal elections?

It isn't, as Section 2(2) of Mr. Cardin's bill says, the Times, Places and Manner Clause, which Arizona v. Inter Tribal Council expressly notes precludes federal authority over voter qualifications (and, indeed, apparently killed Oregon v. Mitchell in the process regarding federal power over voter qualifications in federal elections).

Section 2(3) of Mr. Cardin's bill cites "[b]asic constitutional principles of fairness and equal protection," which is not exactly a basis for legislative authority. The third sentence of the section cites the 13th, 14th, 15th, 24th, and 26th amendments empowering "Congress to enact measures to protect the right to vote in Federal [ed: this power also extends to state] elections," which is true, but does not necessarily (except, see below) empower Congress to enforce qualifications regarding felon status. And the third sentence of the section cites the 8th Amendment's ban on cruel and unusual punishments, which is certainly correct, but, alas, does not empower of Congress.

Section 2(4)(C) or Mr. Cardin's bill notes that felon disenfranchisement law "disproportionately impact racial and ethnic minorities," (see also Section 2(10)-(11)), which is certainly the case--the harder question, under existing Supreme Court jurisprudence, is whether a racially disparate impact is a sufficient basis for the exercise of congressional power to expand voter qualifications under the Reconstruction Amendments--which, I think, is a great question, and would likely fracture the majority that wrote the statements in Inter Tribal regarding the congressional power over voter qualifications.

So that's, I think, the best possible constitutional hook for Mr. Cardin's bill.

Mr. Cardin's bill would enfranchise all ex-felons, violent, non-violent, and those who convicted of an election-related felony.

Mr. Paul's bill does something different.

First, Mr. Paul's bill extends only to "non-violent" ex-felons, "non-violent" meaning crimes that defined as crimes of violence under 18 U.S.C. § 16 and analogous state laws.

Second, Mr. Paul's bill excludes felons serving a term in prison from the scope of his bill, and those serving a term of probation if it's less than one year (or the first year of a longer probation term). Mr. Cardin's bill extends to enfranchise those who are serving a term of probation.

Third, Mr. Paul's bill includes no mention of a constitutional basis for enacting this law.

Given Mr. Paul's abiding concern over the scope of federal authority in other areas, I found the complete lack of any constitutional hook as a slight surprise.

Perhaps Mr. Paul would rely on similar constitutional bases as Mr. Cardin, but he would run into some of the same problems. At best--in my own understanding of the Constitution's authority granted to the federal government--he might be able to argue that the disparate impact of felon voting laws on racial minorities would authorize Congress to enact this law, pursuant to its power under the Reconstruction Amendments.

But that constitutional claim is not made explicitly. And we are left merely to guess.

Portions of this post originally appeared in emails sent to the Election Law listserv.