James Varney:

It was a prolonged mystery that struck Wisconsin education reformers as more akin to a Kafka novel than American due process: Who was behind cryptic demand letters sent under the aegis of the Obama Justice Department, intimating without specific evidence that Milwaukee’s school-choice program was illegally discriminating against disabled kids?

Now, after a six-year bureaucratic and legal tangle in which school voucher advocates said they were stonewalled by Washington, the mystery has been solved. And the answer, they say, is alarming: The federal operation was sparked and practically run behind the scenes by liberal opponents of the program.

Documents released in December through litigation by school-choice advocates showed that lawyers with the American Civil Liberties Union and Disability Rights Wisconsin had prodded federal prosecutors to go after the program, which enables low- and moderate-income Milwaukee parents to use taxpayer-funded vouchers to send their children to private schools. Nearly 30,000 students participate in the program.

According to the documents, the liberal groups opposing vouchers coordinated media strategy with the feds and submitted questions that Justice turned around and posed nearly verbatim to Wisconsin education officials. In addition to suggesting that the program was violating the Americans with Disabilities Act by denying access to disabled kids, the groups promised to drum up additional complaints. Their efforts appear to be why Justice kept the inquiry open for four years even though federal and state officials asserted from the start that, even if the unproven charges were true, they were not legally empowered to remedy them in private schools.

Much more on vouchers, here.