In the name of civil rights, the Department of Justice is trying to prevent black families from exercising school choice.

On the heels of the Southern Poverty Law Center’s ridiculous lawsuit against Alabama’s new school choice law, which contends that if a law doesn’t help everyone it can’t help anyone, the U.S. Department of Justice is suing to block the state of Louisiana’s school voucher program for low-income students and students assigned to failing public schools:

The Justice Department’s primary argument is that letting students leave for vouchered private schools can disrupt the racial balance in public school systems that desegregation orders are meant to protect. Those orders almost always set rules for student transfers with the school system.

Federal analysis found that last year’s Louisiana vouchers increased racial imbalance in 34 historically segregated public schools in 13 systems. The Justice Department goes so far as to charge that in some of those schools, “the loss of students through the voucher program reversed much of the progress made toward integration.”

Segregation! That’s a serious charge. What evidence does the Department of Justice cite?

In Tangipahoa Parish, for instance, Independence Elementary School lost five white students to voucher schools, the petition states. The consequent change in the percent of enrolled white students “reinforc(ed) the racial identity of the school as a black school.”

Five students! According to the National Center for Education Statistics (NCES), there were 143 white students out of 482 students at Independence Elementary School in 2010-11 (the most recent year for which data is available). Assuming that recent enrollment and racial composition is the same and that no black students received vouchers as well, that’s a 0.7 percentage point shift from 29.6 percent white to 28.9 percent white. Though the students at Independence almost certainly would not have noticed a difference, the racial bean counters at the DOJ see worsening segregation.

But the DOJ is not content merely to prevent white students from exercising school choice. The petition also cites Cecilia Primary School, which in 2012–13 “lost six black students as a result of the voucher program,” thereby “reinforcing the school’s racial identity as a white school in a predominantly black school district.” In the previous school year, the school’s racial composition was 30.1 percent black, which the DOJ notes was 16.4 percentage points lower than the black composition of the district as a whole. According to the NCES, in 2010-11 there were 205 black students out of a total enrollment of 758, so the school was 27 percent black. Assuming a constant total enrollment, the DOJ’s numbers suggest that there were 228 black students in 2011-12. The loss of six black students would mean the school’s racial composition shifted from 30.1 percent black to 29.2 percent black as a result of the voucher program. Again, imperceptible to the untrained eye but a grave threat to racial harmony according to the Obama administration’s Department of Justice.

These are the only two schools cited directly in the DOJ’s petition, so presumably they represent the two cases with the largest impact. A footnote reveals that “The net loss ranged up to thirteen students per school.”

Since the vast majority of voucher students are black, it is likely that the DOJ’s lawsuit would disproportionately prevent black students from enrolling in the schools of their choice.

State Education Superintendent John White took issue with the suit’s primary argument and its characterization of the program. Almost all the students using vouchers are black, he said. Given that framework, “it’s a little ridiculous” to argue that students’ departure to voucher schools makes their home school systems less white, he said. He also thought it ironic that rules set up to combat racism were being called on to keep black students in failing schools. […]

White also pointed out that the schools in the voucher program must comply with the terms of 1975 court case, Brumfield v. Dodd, that prohibits the state from giving public money to private schools that uphold segregation or discrimination.

It’s no wonder that just a few months ago, more than one thousand people attended the Black Alliance for Educational Options rally to support the program in the face of another legal challenge.

This isn’t the first time that opponents of school choice have tried to use the specter of segregation to prevent families from exercising choice, but the evidence doesn’t support their claims. According to a literature review from the Friedman Foundation for Educational Choice, school choice programs thus far have had the salutary effect of reducing segregation:

Eight empirical studies have examined school choice and racial segregation in schools. Of these, seven find that school choice moves students from more segregated schools into less segregated schools. One finds no net effect on segregation from school choice. No empirical study has found that choice increases racial segregation.

One of the problems with much of the discourse over segregation in education stems from the way it is defined. The Department of Justice here assumes that a school is segregated if its racial makeup varies from the population in that district. While most sane people wouldn’t consider a school that is roughly two-thirds white and one-third black or vice versa to be segregated, the Department of Justice does so long as the general population of the district is even more racially imbalanced. As the Friedman literature review notes:

[Professor Jay P.] Greene provides an instructive example that shows how this problem undermines the validity of such measures of segregation. In studies using the prevailing method, a school that is 98 percent white is considered perfectly integrated if it is in a school district that also is 98 percent white. The school receives this perfect score even if the 98-percent-white school district is right next door to another district that is 98 percent minority. Clearly, this should be considered segregation, but the prevailing method masks segregation when it occurs at the district level. Greene issues a concise verdict on what studies like this really are saying: “The schools are well integrated, given that they are horribly segregated.”

The studies included in the aforementioned Friedman Foundation literature review use more valid methods of measuring segregation, such as comparing the racial composition of a school to the racial composition of the wider metropolitan area (not just the school district), or measuring the occurrence of racial homogeneity.

School choice programs benefit most those who previously had the fewest educational options, particularly low-income families. Minority groups that are disproportionately low-income therefore benefit disproportionately from school choice. As the Friedman study notes, Milwaukee’s private schools were 75 percent white in 1994, but by 2008 they were only 35 percent white due to the city’s voucher program.

The Department of Justice’s lawsuit will hurt the very students it is intended to help. If DOJ apparatchiks want to reduce segregation in education, they should support efforts to expand school choice rather than try to block them.