Supreme Court Justice Clarence Thomas, in the opinion he wrote on the Supreme Court’s recent decision about two abortion laws, argued that the door for abortion rights was opened by the eugenics movement. (Charles Dharapak, File)

In the opinion he wrote on the Supreme Court’s recent decision about two abortion laws, Justice Clarence Thomas reached back into history.

Thomas argued that the door for abortion rights was opened by the eugenics movement — the now-discredited pseudoscience obsessed with the genetic fitness of white Americans that was popular in the early 20th century — to raise alarm about abortion rights now.

He wrote that “abortion is an act rife with the potential for eugenic manipulation.”

“From the beginning, birth control and abortion were promoted as a means of effectuating eugenics,” he wrote.

It was a bold case that argued of the dangers of abortion — a new chapter in the nation’s highest court in the push to outlaw abortion, and, many noted, given the way Thomas wrote about it, potentially even birth control.

But historians say that Thomas’s 20-page opinion distorts history in the service of ideology. The Washington Post spoke to seven scholars of the eugenics movement; all of them said that Thomas’s use of this history was deeply flawed.

“Thomas is guilty of a gross misuse of historical facts, and especially in the U.S. context,” Philippa Levine, a history professor at the University of Texas at Austin, wrote in an email.

Thomas C. Leonard, an economist and historian at Princeton University and the author of a book about the eugenics movement, said it was an “amateur historical mistake to project early 21st-century right-wing views” onto the early 20th century.

“Forget what it means from a constitutional law perspective,” he told The Post. “It’s really bad history.”

Paul A. Lombardo, a professor of law at Georgia State University who has written extensively about the eugenics movement, said that he thought Thomas’s opinion was “historically incoherent.”

Daniel Kevles, a professor emeritus at Yale University with expertise in the history of medicine, said it was “ignorant and prejudiced when it comes to birth control and wholly inappropriate when it comes to abortion, vis-à-vis eugenics.”

Adam Cohen, a lawyer and journalist who wrote a book about a famous eugenics case the Supreme Court ruled on in the 1920s that was cited by Thomas some dozen times in the opinion, offered a similar rebuke of Thomas’s argument.

“It’s just not historical,” Cohen told The Post.

All said that Thomas’s opinion seemed to mischaracterize the history of the eugenics movement, which flourished in the United States in the early part of the 20th century. While it consisted of a wide constellation of groups and individuals, leading eugenicists and organizations of the day were largely opposed to abortion and birth control, they said.

Charles Davenport, a biologist and the most famous eugenicist of the early 1900s, was against birth control, as was Theodore Roosevelt, another prominent proponent of eugenics — fearing that birth control would only be used by wealthy women and thus have the opposite effect of promoting the genetic proliferation of the people that many eugenicists supported, professors said.

“Eugenicists were initially hostile to birth control because they knew that the women who would use it were the type of women they would want to encourage to reproduce, so-called ‘better’ women — upper-middle-class women,” said Kevles, the Yale professor. “When they finally came around to it, they did it in the face of a practical reality — they caught up to what their constituency was doing.”

And abortion found even less support among this group. The American Eugenics Society regarded it as murder, Kevles said. Davenport and Harry Laughlin, another one of the movement’s leaders, both were strongly against it.

“I’ve been studying this stuff for 40 years, and I’ve never been able to find a leader of the eugenics movement that came out and said they supported abortion,” Lombardo said.

Thomas cited high rate of abortion for fetuses diagnosed with Down syndrome in developed countries (98 percent in Denmark, 90 percent in the United Kingdom, 77 percent in France and 67 percent in the United States, according to the statistics he cites), the practice of sex-based abortions in Asia (to eliminate female fetuses), and statistics that show higher rates of abortion among blacks than whites, to make his argument that abortion is akin to eugenics.

But many of the historians were quick to point out that abortion — a personal choice by an individual — differed significantly from the state-mandated programs foisted involuntarily on others by eugenicists.

Laws mandating involuntary sterilizations for certain sectors of the population that were deemed unfit — those who were mentally ill or physically disabled, or had criminal records, for example — were passed in 32 states.

“Eugenics was about state control of human breeding . . . A platoon of scientific experts would decide what’s best for the human genome,” said Leonard, the Princeton historian. “Today it’s very different. We leave the decision to parents and medical professionals, and that makes all the difference.”

Some said they felt that eugenics laws had more in common with the antiabortion movement, which has pushed for state policies — including many that are being passed around the country — that restrict women’s choices regarding their pregnancies.

“That’s the through line that I see, in terms of state-mandated reproductive control,” University of Michigan history professor Alexandra Minna Stern said.

Thomas also mentioned the eugenicist views of Planned Parenthood founder and birth-control activist Margaret Sanger, a frequent boogeyman for antiabortion activists on the right, at length in his opinion.

Sanger made advocating birth control a central focus of her life’s work, though she did not look kindly upon abortion, a point that Thomas concedes. But he takes aim at her nonetheless, emphasizing the eugenicist views she dabbled in as her career went on and the fact that she opened a birth-control clinic in Harlem. The implication is that Sanger wanted to limit the growth of the black community — a point multiple scholars said was misleading.

“I have to stress that her concern with lower income and immigrant women was to give them control of their lives; and these women were extremely grateful for it,” Kevles said. “Thomas extraordinarily distorts the story.”

Ayah Nuriddin, a PhD candidate at Johns Hopkins University who is writing her thesis on eugenics and the African American community, agreed.

“History shows that a lot of African Americans thought Margaret Sanger had the right idea,” Nuriddin said. “That birth control is not only a way to control reproduction and family size, but also a lot saw it as a vindication of black womanhood, coming out of a long history where, during slavery, a lot of black women didn’t have control over their reproduction due to all kinds of horrific sexual violence.”

Books by both Cohen and Lombardo were cited in the opinion; both felt as though their work had been misused, an experience Cohen wrote about in the Atlantic.

“It was absolutely decontextualized,” Lombardo said, of his book “Three Generations, No Imbeciles: Eugenics, the Supreme Court, and Buck v. Bell.”

Thomas had some defenders.

Conservative legal activist Ed Whelan took aim at Cohen’s critique of Thomas.

“Cohen’s essay is just another in the sorry genre of ‘you properly cited my work in the course of an argument I don’t agree with,’” Whelan wrote at the National Review.

The Supreme Court decision in the case for which Thomas wrote his opinion was largely seen as a compromise.

The court upheld an Indiana law that mandated that the tissue from an abortion or miscarriage be buried or cremated, like other human remains. But it said that it would not revive another part of the law, struck down by a lower court, that would have prohibited abortions if the woman chose the procedure because of a diagnosis or potential diagnosis of Down syndrome or any other disability, or because of the fetus’s gender.

Thomas’s focus on eugenics followed other conservative arguments in the case; an amicus brief filed by 18 states on Indiana’s behalf argued that the state had the duty to protect fetuses with Down syndrome “from wholesale elimination by eugenic practices.” And the argument was touched on by a dissenting judge on the appeals court that struck down the laws.

Stern, the University of Michigan professor, said she felt that women were largely absent from Thomas’s opinion.

“The use of this kind of guilt by association, the discursive use of eugenics to smear anything remotely associated with it, or could be associated with it, has been going on a long time. You don’t have to go that much further in his argument to criticize Darwin and theories of evolution, and therefore eugenics, and sterilization, therefore Nazism, and therefore birth control,” she said. “This has been part of the sensationalist rhetoric of antiabortion activists for a long time. What is striking about this is that this is now in an opinion by a Supreme Court justice.”

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