Abortion opponents regularly talk as though no restriction is off the table when it comes to stripping away reproductive rights. And supporters of abortion rights don’t always set them straight. If we don’t know what our established rights are, we can’t defend them. Pro-choicers need to know why abortion is a constitutional right and what boundaries the U.S. Supreme Court has set out to protect it.

1. Abortion is protected by the rights to bodily integrity and to make decisions about family. The Court explained that decades ago.

The 14th Amendment prohibits states from depriving a person of liberty without due process of law. A person has the right to end a pregnancy without undue interference from the government because that right to liberty includes (1) the right to make decisions about family and (2) the right to bodily integrity.

However, in order to portray abortion rights as illegitimate, conservatives like to argue—inaccurately—that the Court legalized abortion in Roe v. Wade by inventing a right to privacy that is not grounded in the Constitution’s actual text.

In the pre-Roe contraception case Griswold v. Connecticut (1965), the Court did hold that “penumbras, formed by emanations” or various interpretations of the First, Third, Fourth, Fifth, and Ninth Amendments protect a right to privacy. But in deciding Roe, the Warren court located the right to privacy in the 14th Amendment’s explicit protection of the right to liberty. Regardless, the Court’s understanding of the rights that protect reproductive freedom expanded beyond just privacy decades ago.

Privacy is barely mentioned in Planned Parenthood v. Casey, which established the current law governing abortion rights more than 20 years ago. “The controlling word in the cases before us is ‘liberty,’” the decision explained. It was settled law prior to Roe that liberty includes “the right to make family decisions and the right to physical autonomy.”

Privacy is also a constitutional right, and it was indeed violated by the laws at issue in Roe and its companion case, Doe v. Bolton. Those laws required a woman seeking an abortion to share her reasons for wanting the procedure with legal or medical authorities to have any hope of receiving legal abortion care. However, the law and discourse around privacy at the time of Roe implied a woman should be permitted to use contraception or end a pregnancy because the state should not interfere in decisions made in secret with the permission of her doctor, husband, father, pastor, or others. Casey instead properly recognized that the 14th Amendment protects a person’s right to control her body and destiny.

So why has the idea persisted that all we’ve got is a privacy right made up out of thin air? A counterintuitive and less textually based right serves abortion opponents, but abortion rights advocates also have a history of telling us abortion restrictions are primarily a threat to privacy. As William Saletan documented in Bearing Right: How Conservatives Won the War on Abortion, in the run-up to Casey, pro-choice leaders emphasized privacy on the advice of pollsters and political consultants to appeal to anti-government, anti-welfare, anti-tax, and anti-integration sentiments. While reproductive rights lawyers argued to the Supreme Court that the Constitution’s protection of autonomy, bodily integrity, and equality protected abortion access, outside of court pro-choice leaders told the public the right at stake was privacy. But, ultimately, the Casey decision provided a much fuller discussion of why abortion is constitutionally protected by rights beyond privacy.

Abortion is protected by the due process clauses of the Fifth Amendment (which restricts the federal government) and the 14th Amendment (which was added to the Constitution to restrict the states). As Casey explained, “It is a promise of the Constitution that there is a realm of personal liberty which the government may not enter.” Using the force of law to compel a person to use her body against her will to bring a pregnancy to term is a violation of her physical autonomy and decisional freedom—which the Constitution does not allow.

2. Any pre-viability ban is unconstitutional. Period.

In Casey, the Supreme Court was asked for the sixth time in a decade to overturn Roe, and the Court essentially said forget it. “We answer the question,” the authors of the controlling opinion wrote, “whether a law designed to further the State’s interest in fetal life which imposes an undue burden on the woman’s decision before fetal viability could be constitutional … The answer is no.”

What part of “no” don’t conservative leaders understand? The state may not prohibit abortion before viability. A pregnancy is generally considered viable around 24 to 26 weeks. But, as the Court has recognized, this is a medical determination specific to each pregnancy—so even a 24-week ban would be unconstitutional. Though states continue to propose 20-week bans, every pre-viability ban that has been challenged in federal court has been struck down. The Supreme Court declined two recent invitations to revisit the viability line, set out in Roe and affirmed in Casey, when the Court was asked to review rulings striking down North Dakota’s six-week ban and Arkansas’ 12-week ban. Not even the late Justice Antonin Scalia or Justice Clarence Thomas (now the Court’s last remaining member who has called for overturning Roe) publicly dissented from the decision not to take the case.

It has been “black letter law”—or an established legal rule—for 40 years that abortion cannot be banned before viability with or without exceptions. The government may not condition whether a woman can have an abortion on whether she can prove she has been raped or her health is endangered because she has an absolute right to one before viability for any reason. When Democrats emphasized, for example, former Republican presidential hopefuls Texas Sen. Ted Cruz‘s or Florida Sen. Marco Rubio’s callousness toward women who want to abort a pregnancy resulting from rape, they may have legitimized the idea that a pre-viability abortion ban with the exceptions Donald Trump supports might be permissible.

Similarly, while it is important to combat the racist stereotypes that animate proposed bans for race- and sex-selective abortion—it should be repeated that requiring any inquiry into a person’s reasons for a pre-viability abortion is flagrantly unconstitutional.

Abortion opponents often try to frame 20-week bans as a moderate compromise. In fact, they are advocating for a radical departure from Roe and Casey’s viability rule.  The Court has been clear that departure will not be forthcoming. So it doesn’t matter if 20-week bans poll well—any pre-viability ban is unconstitutional.

But Democrats who are asked what’s wrong with banning abortion after 20 weeks often talk about health conditions and deference to a woman’s doctor. There is little use in explaining the reasons patients need later abortions to proponents of bans intended to vilify women who have them—that only perpetuates the idea that every possible policy is still up for debate because there are no constitutional boundaries.

And when Democrats, asked questions meant to paint them as extremists, fail to give a straight answer to whether abortion can be prohibited at any point in pregnancy, they miss the opportunity to give an apparently much-needed reminder that—say it with me—pre-viability bans are unconstitutional. In Hillary Clinton’s response to Rubio’s claim that she supports abortion being legal “on the baby’s due date,” for example, Clinton said Rubio should know Roe has guidelines. She didn’t, however, say what they are: A woman has the right to end a pregnancy before viability or if it endangers her health. States can prohibit abortions after viability, and most of them do. That is not to say they should. The idea that women wait until the third trimester to abort healthy pregnancies is a myth; women prefer to have very early abortions, and third-trimester abortions are generally unavailable because only a handful of doctors provide them.

Leading Democrats should not have trouble answering questions about abortion. Democratic National Committee Chair Debbi Wasserman Schultz, who has wrung her hands about young women not understanding the importance of Roe, would do well to make sure she can answer ridiculous questions about “abortions at eight months” with Roe basics herself. That would also be preferable to Nancy Pelosi debating what “abortion on demand” means and whether she supports it. When abortion opponents raise the specter of later abortions to shame women, Democrats should tell them states are constitutionally free to ban post-viability abortions that almost no one is having.

When we can’t explain as basic a rule as “no pre-viability bans,” we invite abortion opponents to move the goalposts. One prominent advocate for gradually re-criminalizing abortion (who claims to be a moderate) argued in the Los Angeles Times that a law banning abortion at 20 weeks might withstand constitutional scrutiny if it also mandated paid maternity leave, because that would make the pregnancy less burdensome. That is an extremely audacious twisting of Casey, which allowed states to enact laws aimed at persuading a woman to carry to term so long as they do not impose an “undue burden” on those seeking an abortion, but was perfectly clear that she has the right to one before viability. The test is whether a restriction makes it unduly burdensome for a woman to get the abortion she is entitled to, not whether it would unduly burden her to be forced by the government to carry to term.

3. Casey‘s “undue burden” standard is a meaningful protection of abortion rights when courts apply it properly. 

Casey changed the standard courts use to determine when an abortion restriction short of a ban is unconstitutional—it did not “kill” Roe. Saying so helps savvy anti-choicers portray the doctrine protecting abortion as weaker than it is and emboldens legislators to pass blatantly unconstitutional laws.

Casey replaced Roe’s trimester framework, which set out different standards for what restrictions are permissible by trimester, with the “undue burden” standard. Under Casey, the government may try to promote potential life from the outset of pregnancy—but only by trying to influence a woman’s decision, not by trying to hinder her once she has made it. A law with the purpose or effect of placing a substantial obstacle in the path of a woman seeking a pre-viability abortion is “an undue burden” on her right and thus unconstitutional.

The provisions of the Texas abortion law challenged in the U.S. Supreme Court case to be decided any day now, Whole Woman’s Health v. Hellerstedt, are clearly unconstitutional; the law requires all abortions to be performed in hospital-like facilities by doctors with hospital admitting privileges. The idea that such provisions are meant to protect women rather than make getting an abortion more difficult and expensive doesn’t pass the laugh test, and the decision of the Fifth Circuit Court of Appeals upholding them is an outlier. Other courts have assessed the evidence and determined that they have no medical benefit—and, thus, the burdens they impose are “undue.”

But in the run-up to Whole Woman’s Health, too many abortion rights supporters have suggested the undue burden standard is toothless, essentially echoing anti-abortion advocates and a rogue appeals court engaged in an obvious attack on the Supreme Court’s precedent. Rather than encouraging the idea that no burden is “undue” unless it is “insurmountable,” abortion rights supporters should embrace an interpretation of the term more consistent with its meaning in the English language, as the majority of courts have. In an opinion striking down Wisconsin’s admitting privileges requirement, Judge Richard Posner of the Seventh Circuit Court of Appeals explained a burden is undue if it is “disproportionate or gratuitous.” Even a slight burden resulting from a medical regulation with no medical benefit is undue. Abortion rights supporters should not indulge the idea that shutting down 75 percent of the clinics in Texas might not be.

This matters because public understanding of the law puts pressure on courts and legislators to uphold it. We have to know our rights if we want them to be protected.