Extensive report from KMUW, Witchita’s NPR station:

Housing half of all U.S. voter registrations, Crosscheck gained national attention this year after Kobach advised President Donald Trump in connection with the president’s false claims of pervasive voter fraud in the 2016 presidential election.

In Kobach’s hands in Kansas, Crosscheck has evolved into a tool for shoring up claims of voter fraud instead of its original intention of keeping voter rolls accurate. And critics say that mission inappropriately targets voters who made innocent mistakes and shouldn’t be criminally charged….

It is illegal, however, to vote in two states during the same election, a law most of us don’t know about. It also very rarely happens. An academic analysis released last month titled “One Person, One Vote,” found that double voting in the 2012 election was 0.02 percent, and likely much lower.

That hasn’t stopped Kobach, who inherited the Crosscheck program when he came into office in 2011 and used it to, not only seek convictions, but to support his unproven claims of high numbers of illegal voting.

During an August 2015 edition of KCUR’s “Statehouse Blend” podcast, Kobach was promoting another of his criticized plans — requiring an ID before voting, a controversial plan he says will catch illegal immigrants; that plan is now being challenged in the courts.

Kobach turned to double voting, which he said was one of the easiest ways to perpetrate voter fraud. He said 125,000 people were registered to vote in Kansas and another state. But that doesn’t jibe with a presentation he gave to the National Association of State Election Directors in 2013 when he said Crosscheck found around 80,000 double registrations from Kansas. And Kobach never answered whether those matching registrations, which are not illegal, lead to double voting, potentially not legal.

Even Kobach’s office admits, in a Crosscheck participation guide given to states, that the system is rife with “false positives and not double votes,” as it only looks for matches of first name, last name and date of birth, so lots of people with common names are found. If each state doesn’t spend the money to investigative all the dual registrations, it could erroneously knock too many names from voter rolls, critics charge.