Education Secretary Betsy DeVos made headlines in June when she reversed former President Barack Obama's policy regarding transgender bathrooms, for which he had issued via a "guidance" letter. Obama had used this tactic to expand federal control over state governments.

DeVos is now being urged to reverse Obama-era disciplinary guidance as well. She should do so. Obama's policy was driven by progressive ideology rather than sound science and research. It is hurting students across the country and demoralizing hardworking teachers.

A new study from the Wisconsin Institute for Law amd Liberty, or WILL, shows that Obama's policy has contributed to a massive decrease in suspensions in Wisconsin public schools, subverted local control over disciplinary policies, and, in cases, made schools and teachers less safe.

WILL's study finds that, since 2008, suspensions in public schools in Wisconsin have decreased by 41 percent, similar to the pattern seen across the country. From the 2011-12 school year to the 2013-14 school year, suspensions dropped nationwide by 20 percent. Since 2011, the Manhattan Institute shows more than 50 of the nation's largest school districts have put in place discipline reforms and 27 states have changed their laws to reduce "exclusionary discipline" (i.e. suspensions).

Our study questions the Obama administration's premise that suspensions are race-based. The Obama administration looked at national data from the Department of Education's Office of Civil Rights collected during the 2013-2014 school year and found that minority students were being suspended at higher rates than white students. Academics disagree about whether these disparities are due to racial biases among educators or to real differences in the behavior of students. While this complex issue is far from settled, the Obama administration came down squarely on one side: It's the fault of discrimination by public schools.

Therefore, in January 2014, the Justice and Education Departments issued a "Dear Colleague" memo in response to this ostensible discrimination, threatening legal action if discipline policies resulted in different suspension rates for white and minority students, or an inordinately high rate of suspensions across the board.

Using thinly veiled threats of federal investigation to coerce schools into reducing suspensions, the feds argued that unlawful discrimination can also occur even if "a policy is neutral on its face — meaning that the policy itself does not mention race — and is administered in an evenhanded manner but has a disparate impact — i.e., a disproportionate and unjustified effect on students of a particular race." Under this theory, treating children equitably could be considered discriminatory if it results in higher rates of suspension for minority students over their white peers.

Our data, however, shows that poverty and disability — not race — are the primary factors that determine whether a student is suspended in the largest Wisconsin school districts. While statewide racial disparity in suspensions appears to have declined, the picture looks different when you zoom in to the district level data. For example, at Milwaukee Public Schools, which serves almost half the state's African-American students, the suspension rate has fallen more for white students than for African-American students.

The data is clear: The Obama administration's actions have made some schools less safe. That same Manhattan Institute report showed the results of teacher surveys across the nation: In Santa Ana, Calif., 65 percent of teachers said the new approach wasn't working. According to 60 percent of teachers in Oklahoma City, the amount and frequency of bad behavior increased after the discipline reforms. And 60 percent of teachers in Baton Rouge, La., reported a rise in violence or violent threats from their students. In Madison, Wis., only 13 percent of teachers responded that these new practices had a positive effect on student behavior.

It is a worthy goal to suspend fewer children. But that goal is best accomplished by empowering local community groups who have an effective track record of reaching at-risk youth. Simply refusing to suspend students who have earned a suspension doesn't solve the underlying problem and it needlessly polarizes the country. School disciplinary policy should be based on sound science and research, not spurious ideological doctrines about race.

This is a problem created by the federal government that only the federal government can undo. Secretary DeVos would do well to continue her record of returning power to the states by rescinding this letter and the Obama-era disciplinary guidance.

Natalie Goodnow is a research fellow and Will Flanders is research director at the Wisconsin Institute for Law and Liberty.

If you would like to write an op-ed for the Washington Examiner, please read our guidelines on submissions.