President-elect Trump's tweet that voter fraud cost him the popular vote set off the inevitable firestorm. But what about it?

Hans von Spakovsky, a former member of the Federal Election Commission, suggests that, while not sufficient to sway the presidential race, illegal voting may swing elections where there is a smaller margin. He adds: we don't really know how much illegal voting occurs in the U.S.

Why don't we know about something so important to the workings of our democracy?

The voter-registration process in almost all states runs on the honor system. The Obama administration has done everything it can to keep the status quo in place. The Obama Justice Department has refused to file a single lawsuit to enforce the requirement of the National Voter Registration Act that states maintain the accuracy of their voter-registration lists.

This despite a 2012 study from the Pew Center on the States estimating that one out of every eight voter registrations is inaccurate, out-of-date or duplicate. About 2.8 million people are registered in more than one state, according to the study, and 1.8 million registered voters are dead. In most places it’s easy to vote under the names of such people with little risk of detection.

The Justice Department has fought efforts to make sure that only U.S. citizens register to vote in Kansas, Arizona, Alabama and Georgia. When in 2015, Kansas began offering voting registration at the same time of naturalization ceremonies, officials learned that quite a few people had already been voting before they became citizens.

In 1996, when Loretta Sanchez beat former representative Bob Dornan by  thousand votes, a recount found that Sanchez had received 624 invalid votes. California makes it very easy for noncitizens to vote: the state provides driver's licenses to those here illegally and does nothing to ascertain the citizenship when people register to vote.

Voting illegally hasn't been that risky. The Electoral Board in Fairfax County, Va., in 2011 referred information on 278 noncitizens registered to vote in the county. Then-Attorney General Eric Holder's Justice Department passed on looking into the matter. About half these people already had voted.  

Old Dominion University and George Mason University found in a 2011 study that 6.4% of the nation’s noncitizens had voted in 2008 and 2.2% in 2010. Von Spakovsky cites other troubling studies. He concludes:

The bottom line is that the honor system doesn’t work. There are people—like those caught voting illegally—who are willing to exploit these weaknesses that damage election integrity.

And let's think about this: why the blindness about this problem,  especially among Democrats who allege racism when states try to make voter IDs mandatory, when it comes to illegal voting? The dismissive attitude has to be ascribed to the fact that Democrats are far more likely to benefit from noncitizen voting.