The Constitution grants states the authority to determine “the Times, Places and Manner of holding Elections,” but Hillary Clinton and John Kerry are pushing a Count Every Vote Act that would, among other things, force states to allow voters to register at the polls and declaring Election Day a federal holiday. And then they want to force every state to let felons vote — even though the 14th Amendment specifically permits states to disfranchise citizens convicted of “participation in rebellion, or other crime.”

Forty-eight states deny the vote to at least some felons; only Vermont and Maine let jailbirds vote. Thirty-three states withhold the right to vote from those on parole. Eight deny felons the vote for life, unless they petition to have their rights restored, and the Clinton-Kerry proposal would force them to enfranchise felons (or “ex-felons,” as Mrs. Clinton misleadingly calls them) once they’ve completed parole.

Mrs. Clinton says she is pushing her bill because she is opposed to “disenfranchisement of legitimate American voters.” But it’s hard not to suspect partisan motives. In a 2003 study, sociologists Christopher Uggen and Jeff Manza found that roughly 4.2 million had been disfranchised nationwide, a third of whom had completed their prison time or parole. Taking into account the lower voter turnout of felons, they concluded that about one-third of them would vote in presidential races and that would have overwhelmingly supported Democratic candidates. Participation by felons, Messrs. Uggen and Manza estimated, also would have allowed Democrats to win a series of key U.S. Senate elections, thus allowing the party to control the Senate continuously from 1986 until at least this January.

Liberals normally avoid partisan arguments in expressing their support for voting by felons. Instead, they point to the disproportionate racial impact. Sometimes they overstate that impact, as Mara Liasson of National Public Radio did last week when she said that “I would expect if you did a study, you would find that probably the vast majority of [felons] are African-American.” In truth, a little more than a third of disfranchised felons are black.

But that hasn’t stopped advocates from raising the specter of Jim Crow. In 2002, the Maryland Legislature restored voting rights to twice-convicted nonviolent felons. The Old Line State already allowed those convicted of one felony to vote after finishing parole. Senator Conway of Baltimore said any restriction was excessive: “We don’t want to go back to Jim Crow. We don’t want to go back to poll taxes. We don’t want to go back to literacy tests.”

Such arguments disturbed many moderate blacks. “By making a race issue of restoring voting rights to convicted felons, they’ve once again convinced many that liberal black Democrats – and probably blacks in general – are soft on, or sympathetic to, criminals,” wrote Gregory Kane, a Baltimore Sun columnist. “That’s why you would never see the NAACP of the Walter White or Roy Wilkins era advocating the restoration of voting rights to convicted felons.”

The allegation that laws restricting felon voting are racially motivated is flawed. Harvard historian Alexander Keyssar, author of the classic book “The Right to Vote,” points out that many states passed such laws before the Civil War. Later, the laws were passed in many Southern states by Reconstruction government run by Republicans who supported black voting rights. Mr. Keyssar says that “most laws that disenfranchised felons had complex and murky origins,” often centering on the notion that “a voter ought to be a moral person.” As one judge noted: “Felons are not disenfranchised based on any immutable characteristic, such as race, but on their conscious decision to commit an act for which they assume the risks of detection and punishment.”

This is not to say that some states don’t take laws against felon voting too far. Some have overly cumbersome procedures for restoring such rights. One could certainly distinguish between nonviolent felons and murderers and rapists. If I sat in a legislature in a state with a lifetime ban, I would probably support restoring the right to vote to those who had completed jail time and parole. I wonder if liberals would similarly back restoration of the right to own a gun to felons who had similarly done their time and finished parole.

In any case, it is the states that should make such decisions, based on local circumstances and debate. And the states are moving. Delaware and New Mexico recently liberalized their laws. In Connecticut, Governor Rowland, a Republican, signed a bill in 2002 that allows felons on parole to vote – a provision he can now take advantage of, since he was forced from office last year and later pleaded guilty to a federal conspiracy charge. Careful and considered deliberation at the state level isn’t enough for Mrs. Clinton and Mr. Kerry. They insist on a one-size-fits-all policy that Peter Kirsanow, a member of the U.S. Commission on Civil Rights, calls “nothing less than the wholesale restoration of voting rights to convicts – and that suggests an agenda that’s more partisan than altruistic.” Republicans in Congress have their own partisan motivations for opposing any enfranchisement of felons. Leaving the matter to the states probably will mean more felons regaining the right to vote than Republicans would like but fewer than Democrats desire. And that’s probably about the right solution.

Mr. Fund is the author of “Stealing Elections: How Voter Fraud Threatens Our Democracy.” To subscribe to the “Political Diary” e-mail newsletter featuring Mr. Fund, please visit www.OpinionJournal.com, from which this column is excerpted. © Dow Jones & Company Inc.