A federal case challenging access to a common abortion pill is reviving discussions about a 150-year-old anti-obscenity law.

In 1873, what's known as the Comstock Act banned multiple items related to sex and reproductive health that many people see as quite ordinary today. Until recently, that law had been largely forgotten or ignored. But it's being cited in the federal case out of Texas that could curb access to the widely used abortion pill mifepristone.

What is the Comstock Act?

The law prohibits using the mail to spread information or materials deemed "obscene." The term "obscenity" wasn't defined, but the statute did explicitly include anything used to cause an abortion.

The official title of the law is much longer, but it's known as the Comstock Act because of a Connecticut man named Anthony Comstock.

Comstock, a former Union soldier from a deeply religious family, became "horrified by the amount of porn and alcohol he saw his fellow soldiers consuming" while serving in the Army, according to Lauren MacIvor Thompson, a historian at Kennesaw State University in Georgia.

And Gillian Frank, a historian of religion and sexuality and a visiting affiliate scholar at Princeton University, says Comstock embraced a devout form of Protestant Christianity that made him skeptical of ordinary people's ability to control their desires.

"He believed that people were easily corrupted and that it was the role of government and moral crusaders to protect them from harmful and corrupting influences," Frank says. "So in order to stamp out vice, he believed there should be an entire legal apparatus in order to impose his particular set of religious morals."

After the Civil War, Thompson says, Comstock wound up in New York and became a "vice reformer" — an activist leading efforts to oppose those types of behaviors. As part of this work, Comstock assembled a large collection of items he found objectionable that he'd obtained in places like brothels and sex shops.

Then he took it all to Washington, D.C., Thompson says.

"[By this time] he has a very extensive collection of porn, sex toys, 'obscene' books and, of course, contraceptive and abortifacient devices," she says. "And he invites the congressmen to come and look at this display of 'shocking' items."

Comstock persuaded Congress to pass restrictions on sending those materials through the mail. Many states also passed their own versions of Comstock laws around this time.

What's the status of these laws today?

Even in the decades after the Comstock Act and similar laws were passed, they were largely unpopular and there were efforts to repeal them, Thompson says. But the Comstock Act was never fully repealed by Congress.

Instead, a long series of court cases eventually overturned much of the Comstock Act, perhaps most famously Griswold v. Connecticut, the U.S. Supreme Court case that legalized contraception in 1965 for married couples. Then in 1971, Congress repealed portions of the law related to birth control.

The rest has been largely ignored or seen as unenforceable because of evolving case law around issues like free speech and privacy rights, according to Frank.

"A lot of the free speech and privacy that we have, especially sexual privacy, was carved out in the shadow of Comstock, in defiance of it," Frank says.

Last year, after the Supreme Court overturned Roe v. Wade, which had guaranteed abortion rights for decades, President Biden's Justice Department issued a memo stating that the Comstock Act does not apply to the mailing of abortion pills as long as the sender intends for them to be used legally. The Food and Drug Administration under Biden has been allowing that since 2021.

How does the Comstock Act play into the federal abortion pill case?

Groups opposed to abortion rights are trying to overturn the FDA's decades-old approval of the abortion pill mifepristone and do away with the recent rule changes that have made the pills more available.

Erin Hawley, an attorney for the plaintiffs, argues that contrary to the Biden administration's interpretation, the Comstock Act does make mailing pills illegal.

"What the Comstock law says is that it is improper to mail things that induce or cause abortions, which is precisely the action the FDA took in 2021 when it permitted the mailing of abortion drugs," Hawley says.

And Matthew Kacsmaryk, the federal judge in Texas, where this case originated, appeared to agree with that argument in his ruling just over a week ago. As this case has been working its way through the federal courts, the 5th U.S. Circuit Court of Appeals also issued a decision that seemed friendly to anti-abortion groups' reading of the Comstock Act.

The Supreme Court has issued an administrative stay in the case until late Wednesday, temporarily preserving access to mifepristone nationwide.

Lorie Chaiten, a senior staff attorney at the American Civil Liberties Union's Reproductive Freedom Project, says anti-abortion activists appear to feel emboldened by last summer's Supreme Court decision and apparently are trying to use the Comstock Act to reopen long-settled questions about sexual health and reproductive rights.

"I think that in a sane world, these kinds of arguments get laughed out of court," Chaiten says.

She says she's optimistic those arguments won't prevail but adds that if they did, it would be "catastrophic" for abortion access.

What would it mean for anti-abortion groups to revive portions of the Comstock Act?

Legal experts note that the language of the Comstock Act is vague and broad; for example, it was once used to ban the distribution of information about birth control as well as devices related to contraception and abortion.

Asked about other potential applications of the Comstock Act, Hawley says she believes it could restrict the mailing of other medical products that are necessary to carry out abortion procedures.

"We haven't focused on that," Hawley says. "But the law does prohibit items that are manufactured for abortions."

That reading of the Comstock Act could have implications for people in all 50 states, says Mary Ziegler, a law professor at the University of California, Davis.

"I cannot underscore how broad the text is," she says. "It could encompass any device used in an abortion."

And that, Ziegler says, could amount to a national ban. In fact, she says citing the Comstock Act is part of an intentional strategy being pushed by some anti-abortion activists.

"Because if you can prosecute anyone for putting anything in the mail related to abortion, there is no abortion in the United States that takes place without something put in the mail," Ziegler says. "There are no abortion providers making DIY drugs and medical devices."