The predominant narrative among education activists is that school segregation has gotten worse in the past several decades. It’s an argument backed by data — one I’ve stressed in my own work. And earlier this year, a New York Times op-ed also made this argument and cited that same data.

But there’s now a handful of pundits pushing back on this notion, like the National Review’s Robert VerBruggen. In response to the Times piece, he wrote that changing demographics makes the data misleading — and that ultimately, “we’re not going in reverse” when it comes to segregation. Prominent journalists, like New York magazine’s Jonathan Chait and my colleague Matt Yglesias, shared VerBruggen’s post on Twitter.

The National Review piece isn’t coming out of the blue. The idea that changing demographics — the US becoming less white — makes it harder to integrate schools is something that has picked up steam in recent years. In Connecticut, Gov. Dannel Malloy has pushed for more leniency in standards set by a court-ordered desegregation case.

So how could two sides look at the data and come to two different conclusions about school segregation trends?

On the surface, this is an argument about how we measure school segregation trends. But ultimately, it’s a disagreement over how we should be thinking about school segregation.

Is school segregation not actually getting worse? It depends on how you measure it.

The core disagreement comes down to federal government data that was highlighted by the UCLA Civil Rights Project on the 60th anniversary of Brown v. Board of Education, the Supreme Court case that ruled segregated schools were unconstitutional.

The data shows that black students in the South are less likely to attend a school that is majority white than about 50 years ago:

National Review’s VerBruggen sees this chart and argues that a smaller portion of black students are attending majority-white schools because the US is just less white than it was 40 or 50 years ago:

Both arguments are the products of some messy data work.

On one hand, if we’re measuring segregation by how many children attend majority-white schools, then it’s worth acknowledging that white people are now a smaller percentage of the US population. This is something I’ve admittedly left out of my work when presenting this data.

On the other hand, VerBruggen uses this flaw to argue that school segregation actually isn’t getting worse — even though it’s virtually impossible to make this argument from this data alone. VerBruggen does cite a study by Stanford sociologist Sean Reardon and USC sociologist Ann Owens that says school segregation hasn’t changed that much in the past few decades. But Reardon and Owens specifically write that there are two ways they measure segregation:

Exposure or isolation, which looks at whether students attend schools with a high or low proportion of a given racial group Unevenness, which measures how evenly distributed students of a given racial group are

Reardon and Owens write, “The debate about whether the last two decades can be characterized as a period of resegregation largely hinges on whether one uses exposure or unevenness measures of segregation.”

The VerBruggen argument adopts the “unevenness” frame: School segregation hasn’t gotten worse because students are just as unevenly distributed now as they were in the 1980s.

Reardon and Owens give this example:

... Consider a school district in which 90% of students are black. If all schools in the district had enrollments that were 90% black, we would have low unevenness but high black isolation (or, equivalently, low black-white exposure) because the average black student would attend a predominantly black school. Conversely, in a school district with very few black students, isolation might be low even if students were very unevenly distributed by race.

But if you care about more equity in education, this is an odd argument. It’s essentially saying: Hey, we haven’t made school segregation worse — and it’s because of Asian and Hispanic immigrants.

This leads to the reason why people who care about equity balance it with the other measure: isolation.

A reason to measure racial isolation, not just unevenness

Let’s just state this for the record: Racial segregation in schools was caused by white America’s policies that kept schools and neighborhoods white-only. For black families, this meant their country engineered for them a second-class experience — one that put them in poor, segregated ghettos and poor, segregated schools.

And that’s not getting better. Black children are now more likely to grow up in poor neighborhoods than they were 50 years ago.

This is important because a large body of research shows that growing up in heavily segregated, poor neighborhoods affects everything from your education level, your future earnings, and your happiness to your health and, ultimately, your life span.

But in many of these areas, where you live determines where you go to school. So when we see students who are racially isolated, it’s describing both underlying residential segregation and how little school districts do to ameliorate that segregation.

As it turns out, things have been getting worse since the 1980s when we look at segregation using this isolation frame:

As Reardon and Owens point out, indices of exposure show black-white segregation have actually gotten worse since the 1970s:

This has caused a growing number of our schools to be predominantly black or Hispanic with a higher concentration of students in poverty:

This isn’t even considering the growing charter school movement. An increasing number of charter schools are high-poverty and are predominantly black or Hispanic. Meanwhile, a growing number of charter schools are also low-poverty and predominantly white and Asian:

So, yes, there is a portion of America that is getting more diverse. And overall, the “unevenness” measure of segregation shows we’re racially distributing students about as well as we were a few decades ago.

But we are also increasingly isolating the most vulnerable students in America. Things haven’t been steady; they are getting worse.

Focusing on what’s holding steady pushes a misleading narrative

VerBruggen is pushing back against a narrative that most experts agree with, which says that America went through a period of desegregation from the 1950s through the 1980s but then backslid in the decades since. VerBruggen is arguing that as immigration policies have diversified America in recent decades, our schools diversified as well.

But research by Cornell sociologist Daniel Lichter shows that segregation between white families and nonwhite families has actually changed very little since the 1980s. In fact, while segregation within cities has gotten slightly better, segregation between municipalities has gotten worse.

In other words, there is probably less segregation within the neighborhoods of your town. But there is probably more segregation in comparing your town and a neighboring one.

So if broader segregation has increased, it might be reflected in our schools, as school attendance zones are often drawn based on where you live.

This is partially what has entrenched the heavily segregated school attendance zones in virtually every American city:

But school boards can draw school attendance boundaries to lessen that segregation — to send kids to less racially segregated schools. We don’t have to send kids to the nearest school, especially because it ends up recreating the underlying residential segregation:

But most school districts don’t do anything to ameliorate this situation. We continue to recreate the residential segregation. (Here’s an interactive that lets you look up your own district.)

In addition, research from Southern Methodist University’s Meredith Richards shows that when neighborhoods don’t experience much demographic change, they tend to draw school attendance zones that resegregate. Also, when neighborhoods experience a lot of demographic change, they defensively draw attendance zones that further segregate:

So let’s rehash here:

We are increasingly isolating poor black and Hispanic children in segregated schools, both public and charter.

Residential segregation between cities is getting worse, and the Supreme Court in the 1974 case Milliken v. Bradley said surrounding cities could not be forced into school integration plans.

Meanwhile, segregation within cities is about the same as in the 1980s. It’s still extremely high.

School districts are doing very little to ameliorate that segregation.

And when neighborhoods don’t change or drastically change, school districts actually tend to make even more segregative attendance zones.

Yes, we can find metrics that show school segregation isn’t getting worse; we can find metrics that show our schools are not any more segregated now than they were 30 years ago. These metrics are important, and they describe significant ways our schools are changing.

And, to be fair, VerBruggen writes in his piece that “this doesn’t mean that this country’s racial problems are over or that there’s nothing we can do to spur further integration.”

But using those metrics to paint a picture in which school segregation isn’t getting worse misses the point of why we talk about school segregation. The American education system has vestiges of engineered inequities, and those inequities have created unequal opportunities for a huge chunk of black Americans. When we query the data using this framework, the answer is clear: We are going in reverse.