Students at the Harlem Children’s Zone. Photo: Jeff Greenberg/UIG via Getty Images

The author Sam Harris has been insisting that Charles Murray’s work on IQ and race has been smeared, or ignored, because liberals hate its political implications. (In case you haven’t followed this debate, Ezra Klein has an excellent summary.) I’ve always found the rebuttals to Murray’s work far more persuasive than Murray’s case. But I am not an expert in genetics or science, and it is hard for me to write about such a technical dispute at the level it requires.

I do, though, have some familiarity with a field that has some bearing on Murray’s claims. Academic achievement is closely related to IQ. Murray himself has treated the two as essentially synonymous, and he has argued that the persistence of the achievement gap demonstrates the genetic durability of the black-white IQ gap.

“The National Assessment of Educational Progress shows a small narrowing of the gap between 1994 and 2012 on its reading test for 9-year-olds and 13-year-olds (each by the equivalent of about 3 IQ points), but hardly any change for 17-year-olds (about 1 IQ-point-equivalent). For the math test, the gap remained effectively unchanged for all three age groups,” he wrote in 2014. “If you want to say that the NAEP and SAT results show an academic achievement gap instead of an IQ gap, that’s fine with me, but it doesn’t change anything. The mean group difference for white and African American young people as they complete high school and head to college or the labor force is effectively unchanged since 1994.” In a 2006 symposium at the American Enterprise Institute (according to a summary by Reason magazine science writer Ronald Bailey), Murray “noted that the programs established by the No Child Left Behind Act have had almost no effect on the black/white educational achievement gap.”

Murray is correct that the black-white academic achievement gap is large and, after a period of closing, has remained stubbornly extant. He cites the failure of No Child Left Behind to close the achievement, as if this one, flawed and underresourced reform proves that no reform could work. But to support his thesis that genetic differences have played a large role, it would have to be the case that the achievement gap cannot be closed. And that is provably wrong.

Over the last decade or so, several educational experiments have demonstrated that well-designed reforms can yield rapid improvement among impoverished minority students. Harvard professors Will Dobbie and Roland Fryer studied the Promise Academy in the Harlem Children’s Zone, which combines intensive community services in health, nutrition, day care, parenting, and so on, alongside innovative instruction with high standards. Their experiment was designed to test whether the right combination of environmental changes could elicit the same academic results from black children as white ones. And they found that it could:

Both lottery and instrumental variable identification strategies suggest that the effects of attending an HCZ middle school are enough to close the black-white achievement gap in mathematics. The effects in elementary school are large enough to close the racial achievement gap in both mathematics and ELA.

Columbia professor Sarah Cohodes studied a broader array of charter schools. She found that the most effective ones, using a “no excuses” method of high-standards pedagogy, could eliminate the achievement gap:

No excuses schools emphasize high expectations for both academics and behavior, longer school days and years, and frequent observations of teachers to give feedback, tutoring, and data-driven instruction that uses assessment to frequently update teachers. In some cases, these charter schools have quite large effects, such that attending one for three years produces test-score gains that are equivalent to the size of the US black-white achievement gap.

These are not studies of selective academies picking off the brightest and most promising students. These are experiments designed to gauge the ability to teach broad populations of poor, nonwhite students. And it is indeed possible to get them to perform as well as white students.

There are intense debates about how extensively these experiments can be scaled up and replicated nationwide. While that debate is relevant to educational policy, it is not relevant to the argument Murray is making. He is insisting that aggregate genetic differences make it impossible to close the achievement gap. Even if it were politically or logistically impossible to reproduce the success of high-performing charters for every urban student — and I would challenge that fatalistic assumption — the fact that they can work shows the impediment is not innate. Within the brains of America’s African-American children is the same innate potential to achieve found in its white children.

I am all for open debate on these questions. But I don’t believe the evidence supports Murray’s conclusions.