They know that the voter rolls are breeding grounds for potential fraud.

Last Thursday, President Trump announced the formation of a bipartisan commission to investigate voter irregularities and fraud as well as charges of voter suppression in America. The hysterical criticism of his move lays bare the ideological conflict of visions raging over efforts to improve our election systems.

Britain’s Guardian newspaper declared the notion of a commission “a white power grab” designed to reduce minority voter turnout. It said that appointing Kansas Secretary of State Kris Kobach to be vice chairman of a group examining election integrity was “like Hitler asking Goebbels to help put out the Reichstag fire.” Dale Ho, director of the ACLU’s Voting Rights Project, said that “the American people should demand that elected officials and election administrators not participate in this phony commission.” Tom Perez, chair of the Democratic National Committee, labeled the commission “a Trump propaganda factory” designed to justify the president’s January claim that he would have won the popular vote if not for 3 million to 5 million illegal votes cast.

Few people believe that Trump’s estimates of illegal votes paint a realistic picture of the issue, and he offered no evidence for his claim. But if he’s wrong, what is the harm of having the first serious national look at just how big the problem might be? If liberal critics are right that voter fraud doesn’t exist save for trace elements, then the commission will come up empty-handed.

Kobach, who last year became the only state election official with the power to prosecute voter fraud, has already pursued nine cases. In 2015, one Kansas county began offering voter registration at naturalization ceremonies, as Hans A. von Spakovsky and I reported in January at Fox News. Election officials soon discovered about a dozen new Americans who were already registered — and who had voted as non-citizens in multiple elections. Kobach says he suspects there are problems in other states. “There’s never actually been a nationwide effort to look at the scope of voter fraud,” he told CNN’s Erin Burnett in April. “Why wouldn’t we want to collect as much data as possible?”

Indeed, smart liberals are already moving away from the mantra that “there is no voter fraud” to a more nuanced position. They know that it’s likely that if Kobach and his fellow commissioners allow states to examine federal databases of permanent legal aliens, holders of temporary visas, or alien filers of tax returns, they will probably find people who are illegally registered to vote — and voting. Kobach told me in an interview that states have tried to run those databases against their own voter-registration lists for years, but the Obama administration turned down all their requests. “Such a study has never been done before,” he told me.

That knowledge is perhaps behind a subtle shift in the statements of some liberals about Trump’s Election Integrity Commission. Nathaniel Persily served as senior research director of Obama’s Presidential Commission on Election Administration. Note that no one demanded that election officials refuse to serve on this commission. Persily told the liberal website Talking Points Memo that “you will find a good number of non-citizens, ex-felons, dead people, and other ineligible voters who are registered” to vote. But he says that “just because ineligible people are registered does not mean they voted.”

True enough, but it sure makes it easier for political operatives in a close vote to round up folks for some last-minute shenanigans, as in the voter-fraud case in St. Louis. Last year, that city’s aging black political machine used absentee-ballot fraud to steal a Democratic primary for state legislator away from 31-year-old Black Lives Matter activist Bruce Franks Jr. In September, a local judge called a new primary election after irregularities in hundreds of absentee ballots were found. Franks went on to win the new election with 71 percent.

Leftists have known for a long time that America’s voter-registration lists are breeding grounds for potential fraud. According to a 2012 Pew Research Center survey, one out of eight American voter registrations is inaccurate, out of date, or a duplicate. Some 2.8 million people are registered in two or more states, and 1.8 million registered voters are dead. Even though that’s a rich vein of potential mischief for fraudsters, the Obama administration didn’t file a single lawsuit in eight years demanding that counties clean up their voter rolls, as they are required to do by the federal “motor voter” law. In 2009, three Justice Department staffers heard deputy assistant attorney general Julie Fernandez say that the DOJ would not be enforcing that provision of the motor-voter law because it ran counter to the law’s overall goal of “increasing turnout.”

That explains why the Democratic line on the new commission is to combine hysterical attacks with cautionary words that what the commission might find won’t be important anyway. “We already know that our voter rolls have mistakes on them,” Myrna Pérez, deputy director of the Democracy Program at the liberal Brennan Center, told Talking Points Memo. “There are ways in which we can clean them up that don’t surprise voters and don’t take eligible people off the rolls.”

All well and good. But that doesn’t explain why Democrats have so often opposed just such efforts at the state level or why the Obama administration for eight years played hide-the-ball with the data it did have on potential ineligible voters. When liberals claim that there is no voter fraud, to borrow Shakespeare’s words, they do protest too much. They know that lurking in our archaic election procedures are problems that need fixing. Here’s hoping the new commission — which includes Democratic secretaries of state Bill Gardner of New Hampshire and Matthew Dunlap of Maine — breaks through and conducts a first-ever national look at the problem.