The Supreme Court concluded in 2008that voter ID is constitutional and doesn’t impose an unreasonable burden on voters. But the recent decisions of three federal courts throwing out voter-ID laws in North Carolina, Texas and Wisconsin as discriminatory have put opponents of common-sense election reforms in raptures. These erroneous rulings twist the Voting Rights Act from a law intended to stop racial discrimination into one that transfers the power to determine routine election procedures—which the Constitution delegates to the states—to the judiciary.

All three rulings share common characteristics, starkly outlined by Fifth U.S. Circuit Court of Appeals Judge Edith H. Jones in her dissent in the Texas case, Veasey v. Abbott . Judge Jones wrote that the majority opinion “misconstrues the law, misapplies the facts, and raises serious constitutional questions.” That indictment applies to the North Carolina (NAACP v. McCrory) and Wisconsin (One Wisconsin Institute v. Thomsen) cases, too.

The majority in the Texas ruling, Judge Jones said, fanned “the flames of perniciously irresponsible racial name-calling” by making “inflammatory and unsupportable charges of racist motivation [that] poison the political atmosphere and tarnish the images of every legislator” in Texas. The “multi-thousand page record yields not a trace, much less a legitimate inference, of racial bias by the Texas Legislature.”

The three-judge panel of the Fourth Circuit Court of Appeals that threw out North Carolina’s election reforms last week engaged in the same type of “perniciously irresponsible racial name-calling” that is not supported by the evidence or common sense. The almost 500-page opinion in April by the district court from which the case was appealed contained detailed factual findings that refute the appeals court’s charges of racial discrimination.

The basic charge is that these state laws were intended to, or would have the effect of, preventing voters, particularly minority voters, from casting ballots. Yet as Judge Jones said, “despite extraordinary efforts to find voters ‘disenfranchised’ by [the Texas law], the DOJ could not uncover any, and no representative of the plaintiff organizations found any of their members unable to vote” because of the law.

The same is true in North Carolina. The Justice Department was contesting that state’s voter-ID law, the elimination of same-day registration and out-of-precinct voting, and the state’s limiting early voting to “only” 10 days. The plaintiffs, in addition to failing to produce witnesses unable to vote because of these changes, produced no voter-turnout information to support their false claims. The actual turnout data show that voters were not kept out of the polls by any of these requirements.

The Justice Department’s so-called experts claimed that turnout would be depressed because—in a patronizingly racist claim that the Fourth Circuit believed—black voters are “less sophisticated” and can’t figure out how to register and vote. But as the district court had already discovered, black voters in North Carolina actually “fared better in terms of registration and turnout rates in 2014, after the new law was implemented, than in 2010, when the old provisions were in place.”

African-American turnout “not only increased, but did so at a greater rate than that of other groups (including whites).” Yet the Fourth Circuit discounted this evidence. The plaintiffs in the Texas case also ignored voter-turnout data for the simple reason that there was no evidence that the law—which was in effect for several elections—affected turnout at all.

This is certainly true in other states, like Georgia and Indiana, where voter- ID laws have been in place for years. None of the bad effects predicted by opponents has occurred. Turnout has not declined. But this actual evidence is ignored in favor of ill-informed speculation and, as Judge Jones said, “unsupportable charges of racist motivation.”

Especially pernicious are the North Carolina and Wisconsin rulings holding that eliminating same-day registration or reducing early voting violates federal law. Early voting didn’t even exist until Texas first adopted it in 1988. The idea that it is discriminatory to have only 10 days of early voting—instead of 20 or 30—is absurd. Under that view, the more than a dozen states that have never implemented early voting are all breaking federal law.

Only about a dozen states offer same-day registration. Everywhere else, you have to register to vote before an election. Yet in the Fourth Circuit’s view, the majority of states that have never implemented same-day registration must also be discriminating in violation of federal law. Also absurd is the court’s opinion that not allowing out-of-precinct voting is discriminatory. Most states have never allowed such voting.

What Judge Jones said in the Texas case applies to all of these decisions: They move “us another step down the road of judicial supremacy by potentially subjecting virtually every voter regulation to litigation in federal court.” This is a road where purposeful racial discrimination “can be ‘inferred’ even without a shred” of evidence. They are prime examples of “unauthorized and extra-legislative transfers of power to the judiciary” that “disable the working of the democratic process.” And harm the security and integrity of the election process.

Mr. von Spakovsky, a senior legal fellow at the Heritage Foundation, and Mr. Fund, a columnist for National Review, are the authors of “Who’s Counting? How Fraudsters and Bureaucrats Put Your Vote at Risk” (Encounter, 2012).