Legal scholar Mary Ziegler explains how another “zombie law” eviscerating civil liberties is stalking the land.

Last week, in a bid to clarify his historically nebulous stance on abortion, Donald Trump said that if reelected, he intends to leave abortion rights “to the states,” seemingly contradicting his prior stance in favor of a 16-week national ban.

But Mary Ziegler, a law professor at UC Davis and leading abortion historian, thinks that a complete ban could be on the agenda for a future Trump administration—and the vehicle for it would be the Comstock Act, a 19th-century anti-obscenity law still on the books. Ziegler and other legal experts warn the law could be marshaled to ban all abortions—even in blue states that protect abortion rights—and possibly even contraception and gender-affirming care, while circumventing the democratic process.

Let’s start with a quick history lesson. In 1873, Congress passed the Comstock Act, which bars the mailing of “every article or thing designed, adapted, or intended for producing abortion, or for any indecent or immoral use.” It was named after anti-vice crusader Anthony Comstock, a Civil War veteran molded by his strict Puritan upbringing who was obsessed with enforcing a culture of sexual purity, which was his mission as a special agent of the US Post Office after the eponymous law was passed. His views on abortion, though, were more nuanced than what the text of the law might suggest: He believed abortion should be permissible to protect a woman’s life.

The act was challenged, narrowed, and broadly seen as irrelevant in the decades after Comstock’s 1915 death, but recently, anti-abortion conservatives have suggested deploying it to skirt the wide support that exists for abortion rights nationwide. They “argue that every abortion involves an item that’s put in the mail or transported by common carrier,” Ziegler said, “and that if there’s this effective mailing ban, that is a de facto ban on [abortion] procedures, full stop.” That would mean a ban on medication and procedural, in-clinic abortions—and, as the health policy research organization KFF, formerly known as the Kaiser Family Foundation, points out in a policy brief, enforcement of the Comstock Act could also affect the treatment of miscarriages and other OB-GYN care.

Anti-abortion activists took that argument to the Supreme Court last month to drastically restrict access to mifepristone, one of the two pills used in medication abortion, which research has shown has continued to grow in popularity since the FDA allowed them to be prescribed virtually and sent by mail starting in December 2021. Project 2025, an initiative led by dozens of conservative groups and spearheaded by the Heritage Foundation, repeatedly cited the Comstock Act—by its statute numbers, not by name—throughout “Mandate for Leadership,” its blueprint for Trump’s next term. Given Comstock, it stated, “the Department of Justice in the next conservative administration should therefore announce its intent to enforce federal law against providers and distributors of [abortion] pills.” Jonathan Mitchell, the conservative lawyer behind the Texas abortion ban, told the New York Times in February, “We don’t need a federal ban when we have Comstock on the books,” cautioning Trump and anti-abortion groups to keep quiet about the Comstock Act until after the election. Trump appears to be following these orders and hasn’t publicly addressed whether he’d enforce Comstock if reelected. (His campaign also didn’t respond to repeated questions about that from Mother Jones.)

These efforts ignore the fact that medication abortion is safe and effective—including when it’s prescribed virtually and mailed to patients—and that polling by the Pew Research Center shows the majority of Americans disapprove of Dobbs and support legal abortion in all or most circumstances. But as Ziegler writes in a forthcoming Yale Law Journal article on the history of the Comstock Act, co-authored with Yale law professor Reva Siegel, “Comstock revival has emerged as a tool to create an abortion ban that would be unachievable in democratic politics—and a vehicle for Republican surrogates to demand a national ban that it would be too politically risky for candidates to assert in their own voices.”

I spoke with Ziegler—who has written six books on the history of abortion and the law in the US—about the Comstock Act, the problems with the right’s reading of it today, Democrats’ strategies (or lack thereof) to resist it, and what the law’s possible revival reveals about the risks posed by similar centuries-old “zombie laws” that could come back to haunt us. Our conversation has been edited for length and clarity.

What was Comstock supposed to accomplish when it was passed back in 1873?

The Comstock Act was passed by a group of people who saw themselves as deeply concerned with sexual purity. This was a period when many Americans were moving to cities; when people from all over the world were immigrating to the United States; when women were campaigning for the right to vote in a way that they really hadn’t before. And this was causing something of a moral panic, particularly among white Protestant well-to-do men who believed that cities were changing the way people, their children, and wives, were behaving. Comstock himself had become particularly concerned about pornography, which he’d been exposed to during the Civil War. But he thought the problem was broader than that. He thought that a broad array of materials—from sex toys to medical textbooks to great works of literature—were all incentivizing people to have impure sex. And this was a concern, I would say, in a different way for women and other female-identified folks because they could get pregnant. But Comstock was concerned with the debauching of boys as well as girls.

Contraception and abortion came into the picture because Comstock believed they made these forms of illicit sex possible. He called them “incentives to crime,” meaning that if you knew you could have this kind of illicit sex without a pregnancy, you’d be more likely to engage in it if you were female. At the time, the law wasn’t very clear about what obscenity meant. No one had really been regulating contraception much at all. Abortion laws were very new and untested, particularly insofar as early pregnancy was concerned. So the Comstock Act basically was designed to stamp out illicit sex…and it spawned a bigger movement. It was not the end of the story. It was sort of the beginning.

You write that “revivalists selectively quote the Comstock law to construct it as an abortion ban, rather than recognizing that the law Congress enacted was a broad obscenity statute, and remains so today.” Can you say more about the problem with their reading of the law? And how does understanding it as an obscenity statute, rather than a plain and simple abortion ban, complicate its application today?

Their argument to the Supreme Court is essentially, “This is the way to a nationwide abortion ban that isn’t about the Constitution, that isn’t about our values, and that isn’t about politics.” It’s sort of a way to give the anti-abortion movement what it wants…and in part, I think this cherry-picking is problematic because if the statute has a plain meaning, it covers much more than abortion.

The other problem…is that I don’t think the statute has a plain meaning. The word “abortion” didn’t have a plain meaning in 1873. [In her paper, Ziegler noted that, at the time, abortion often referred to miscarriages.] I don’t think it has a plain meaning today. And if the statute is ambiguous, then what you’re doing is imposing a 21st-century reading of the statute as a ban they would never enact, which it is not. Reading the text—it’s doing something very different.

You write that when Comstock was passed, “Congress was enacting a law that would be flatly unconstitutional today.” How so, and why do you think we aren’t seeing more Democrats mobilizing to resist it?

The Comstock Act applies not only to items but to speech. Even in the mifepristone Supreme Court case, Clarence Thomas asked, “Wouldn’t information about this pill be illegal under the Comstock Act?” So a lot of speech was covered by the Comstock Act—that’s one potential dimension of a challenge. There are also due process questions about what the heck the terms in the Comstock Act mean. I think the term “abortion” is ambiguous because anti-abortion leaders have contested its meaning and have offered literally dozens of definitions and state laws that vary from place to place.

But there are other terms that I would imagine anyone would agree are vague—like, the statute says you can’t mail items. What does that mean? Does that mean medical textbooks? Does that mean Viagra? Does that mean drugs for gender-affirming care? Does that mean methotrexate, because you could theoretically use it as an abortifacient? Does it mean vaccines? So there are also due process questions raised because you can’t criminally punish someone for violating the rules when they don’t know what the rules are.

There is an interesting interplay between the litigation groups, which really don’t want Democrats going full tilt on the argument that Comstock is going to function as an abortion ban. They think that’s a ridiculous argument legally and don’t want to give it more momentum by having everyone believe that conservatives are right about how the Comstock Act operates. They don’t want that before the Supreme Court weighs in, because they could, in theory, adopt this theory of the Comstock Act. At the same time, Democrats are aware that there’s a real political threat in not discussing Comstock.

So my guess is that after the mifepristone case is resolved, you’ll see a more forceful response from Democrats who’ve been trying to balance not wanting to give conservatives a leg up in the conservative Supreme Court, where they already have an advantage, and not leaving voters in the dark about the threat Comstock poses. I don’t know if they’ve been striking the right balance. Essentially, litigation is pulling one way and the politics are pulling another way.

I didn’t realize this until I read what you wrote, but there was no mention of Comstock in the Supreme Court’s 2022 Dobbs ruling to overturn Roe v. Wade—or even in the privacy-related decisions that flowed from Roe. But a couple of the justices brought it up in the case they heard last month seeking to restrict medication abortion. Why do you think the right didn’t invoke Comstock sooner? Why are they doing it now?

I mean, it’s not a great idea politically to bring it up now, right? I would sort of pose the question of, why would you bring it up at all? [Laughs.]

Politically, it seems pretty disastrous. I mean, Anthony Comstock was a very strange, troubled man who introduced a law that raised grave First Amendment and equal protection concerns, which was enforced against his political enemies in ways that swept in a lot of stuff unrelated to abortion. And you have conservatives for decades spending time creating a single-issue anti-abortion movement, saying, “We are not the sex police. We are not coming for contraception. We are not worried about women voting. We are not concerned about sex outside of marriage. That’s just not our thing. We’re worried about the rights of the unborn here.” So invoking Comstock really undermines that message because Comstock is unambiguously about more than abortion.

The other thing is that enforcing it would have been unconstitutional under Roe. So there was no point in bringing it up. There was both a pretty high political cost of invoking Comstock and not much upside. The other thing that’s important to mention is if you’re thinking of the anti-abortion movement as a single-issue movement, for a long time, its game plan was a constitutional personhood amendment. That was the end goal. And to get a constitutional amendment, you need to win hearts and minds. You need to convince a majority of Americans that you’re right. And invoking the Comstock Act is not going to help you with that. I think we’ve seen a little bit of a pivot since Dobbs toward imagining that fetal personhood will come from a judicial decision from the US Supreme Court, not from a constitutional amendment. If your goal is to win via the courts, you don’t need to care as much about whether voters are with you—or not. So I think to some degree, the invocation of the Comstock Act tells you that the anti-abortion movement has been moving away from strategies that focus on winning in elections and instead on strategies that are taking the issue away from voters and putting it in the hands of people who are not accountable to voters.

You raised earlier the question of what exactly Comstock could regulate. Would the question of what it regulates ultimately depend on how the Department of Justice enforces it?

Absolutely. We don’t know a lot about how it would be interpreted. Contraceptives, I think, would be on the table, because we know that a lot of abortion opponents believe that at least IUDs, the birth control pill, and the morning-after pill are abortifacients. If Comstock is interpreted as an abortion ban, you would have some contraceptives potentially swept in—emergency contraceptives are the most likely. I mean, we don’t know, right? Because the law is very vague, and it would depend on what the Trump Justice Department’s priorities will be. We know that in Project 2025, the priority has been people who manufacture pills and abortion providers who have been called out as prosecution targets. But what actually happens would be left a lot to the prosecutorial discretion of the Justice Department.

The recent ruling from the Arizona Supreme Court reignites this question of “zombie laws” like Comstock and how they can come back to haunt us. I read a piece in the Washington Post that laid out some of these discriminatory laws that are still on the books: 13 states have laws that ban same-sex marriage, and another dozen states ban sodomy. How likely is it that we could see laws like those revived, given that Clarence Thomas has called for overruling the decisions keeping them at bay? Are there other disturbing zombie laws we should be aware of?

Any of what you could imagine as “morals laws” are still on the books. The dynamic, essentially, was the same with Comstock, which is that at a certain point everyone said, “Well, that’s Comstockery,” which meant Victorian, antiquated, prudish. And no one really thought they would be enforced. But then repealing them felt weird because that somehow seemed to be saying, “This kind of sex is OK.” It felt very different for legislators to say, “Well, we don’t want to repeal this ban on sodomy because that makes it seem like we’re saying sodomy is good. But we’re not going to enforce it because that would make us seem like we’re engaging in Comstockery.”

Then you had other people, Democrats essentially, saying over and over again, “Maybe we don’t need to repeal this stuff because it’s not going to be enforced anyway.” And it’s not that they thought it was OK, or they didn’t want to be seen as opposing those things, but rather that they had other priorities. So you would have these zombie laws left on the books time after time because people were prioritizing other things. One of the lessons, obviously, is that that’s a stupid idea—if a law looks dangerous in theory, it can become dangerous in practice.

If Comstock were enforced, could it pave the way for the formal recognition of fetal personhood? And conversely, could states that explicitly protect abortion rights—like New York or California—challenge Comstock’s enforcement?

Comstock is interestingly not about fetal personhood—I mean, Anthony Comstock would occasionally call abortion “antenatal murder,” but it was mostly about sex for him. Sex was the main problem, and abortion was an issue because it let people have sex. It wasn’t that abortion was an issue because of fetal protection. Comstock, if anything, was more worked up about things like dildos than he was about abortion to begin with. Reviving the Comstock Act would be an abortion ban, but the history and language of the statute aren’t fetal protective in the same way at all. From the anti-abortion movement standpoint, Comstock is clearly a stopgap solution because they want recognition that fetuses are persons. That is what leaders of the movement call the new North Star, the new kind of fight that replaced the fight to get rid of Roe v. Wade.

It would certainly move the needle in terms of making abortion harder. Because if the Comstock Act were being enforced, it would preempt state laws that protect abortion rights, and states that have ballot initiatives, and states that have other protective legislation. And I think that’s a really important point for people to sit with for a minute. Because if you don’t like Joe Biden, and you are planning on staying home, and you think that that’s going to be okay if you support abortion rights because you live in a state that either has, had, or will have a ballot initiative, that ignores the fact that the Trump could get elected, enforce the Comstock Act as a ban, and override whatever protections are in your state.

Trump has never said he’s not going to do that—you have a lot of former Trump officials who have been going around essentially promising that he is going to enforce the Comstock Act as a ban. The Trump campaign has never disavowed those claims, never really even addressed those claims. I don’t know that that’s what’s going to happen, but at least it’s a reasonable concern to have, given that Trump has done nothing to discourage those concerns.