The false god of school vouchers has been unmasked once again, this time by a Brookings Institution study that says students in Louisiana and Indiana using vouchers to attend private and religious schools ended up doing worse on reading and math scores than their public school counterparts.

“The magnitudes of the negative impacts were large,” said the study on “The Negative Effects of School Vouchers,” written by Mark Dynarski, a fellow with Brookings’ Center on Children and Families. They also could not be explained away by the nature of the tests the children were taken or by some notion that some of the voucher children had been pulled away from above-average public schools.

Rather, the conclusion that these results point to is that “our historical understanding of the superior performance of private schools is no longer accurate,” Dynarski writes.

The facts in this report strike at a core argument behind the conservative drive to defund public schools and to promote “school choice” to parents, using taxpayer dollars to pay some or all of the costs of a private, often church-based, school. Sometimes invoking the language of the civil rights movement, these voucher programs are defended as ways to liberate students from the mediocrity of public schools and give them the opportunity to get higher quality schooling that equips them to succeed, including if they face barriers of race or class.

Here’s the reality, according to the report: “In Louisiana, a public school student who was average in math (at the 50th percentile) and began attending a private school using a voucher declined to the 34th percentile after one year. If that student was in third, fourth, or fifth grade, the decline was steeper, to the 26th percentile. Reading declined, too: a student at the 50th percentile in reading declined to about the 46th percentile. In Indiana, a student who had entered a private school with a math score at the 50th percentile declined to the 44th percentile after one year.”

Fifteen states and the District of Columbia has school voucher programs. The District’s program is unique in that it is a federally funded (and for many D.C. results, unwanted) intrusion into the city’s affairs. Vouchers have recently made news in North Carolina, where the state legislature is considering a $10 million increase each year in its $12 million budget for the program. That would in 10 years increase the school voucher budget to $135 million.

As Dynarski notes, comparisons of how well students using vouchers to attend private schools in all of these states have done to public school students “have reported mixed results on scores.” But what is remarkable about what the Brookings study saw in Louisiana and Indiana is that earlier studies have not reported “significant negative effects on test scores.”

“In education as in medicine, ‘first, do no harm’ is a powerful guiding principle,” Dynarski concludes. “A case to use taxpayer funds to send children of low-income parents to private schools is based on an expectation that the outcome will be positive. These recent findings point in the other direction.”

But perhaps what is also being unmasked here is that the school voucher movement is not all about academic excellence, at least as education policymakers and experts think of it. Jeff Bryant exposed this several weeks ago in his extensive review of voucher programs and the instruction that gets subsidized by them. An editorial published recently in The Washington Times offers a window into what’s really driving the voucher movement, as it touts vouchers as a way for parents to avoid schools with such mandates as allowing transgender students to use the restrooms that conform to their gender identity. Instead of having to send their children to “schools which they believe promote unsafe and immoral behavior” – presumably such as respect and understanding for people who are different from themselves – the government can instead subsidize “the freedom to choose” a “morality” of intolerance.

But tax dollars should not be subsidizing ignorance of the basic facts of life – whether that ignorance is of how to solve a math equation or how to deal with children who don’t fit our false notions of a gender binary. At the very least, parents should have a fact-based debate of what we’re actually buying with school vouchers, not one argued on faith without evidence.

This blog originally appeared at ourfuture.org on May 26, 2016, Reprinted with permission.