Abortion was made illegal in the United States by state legislatures, acting in two distinct waves separated by nearly a century of federal constitutional protection. The first wave ran through the mid-to-late 1800s, when state lawmakers, pressed by the American Medical Association, replaced permissive common law with criminal statutes. Those bans sat unenforceable from 1973 onward under Roe v. Wade. The second wave arrived in June 2022, when a 6-3 Supreme Court majority in Dobbs v. Jackson Women’s Health Organization overturned Roe and returned the question to the states, many of which had bans already drafted and waiting.
Before Criminalization: The Common Law Baseline
For most of early American history, abortion was governed by English common law, which generally permitted the procedure before “quickening” — the point when a pregnant person first felt fetal movement, usually in the fourth or fifth month. Before that threshold, ending a pregnancy was legally and socially unremarkable. The few restrictions that existed were aimed at protecting the mother’s health, not the status of the fetus.
The 19th-Century Push by the American Medical Association
The organized campaign to outlaw abortion began in the mid-1800s and was led by the American Medical Association, founded in 1847.1American Medical Association. AMA History The AMA was working to professionalize medicine and to consolidate authority over who could practice it. That effort had a direct competitive target: midwives, nurses, and other non-physician practitioners who provided reproductive care, including abortions. Criminalizing the procedure allowed AMA physicians to claim scientific authority while sidelining those competitors.
Dr. Horatio Storer, an AMA member, led the charge. He argued that the quickening distinction was medically baseless and that life began at conception. In 1857, the AMA launched a letter-writing campaign pressuring state lawmakers to ban abortion outright. It worked. More than 40 anti-abortion statutes were enacted between 1860 and 1880, eliminating the quickening distinction and criminalizing abortion at every stage of pregnancy.2Legal Information Institute. Dobbs v Jackson Womens Health Organization (2022) By the time the Fourteenth Amendment was adopted in 1868, three-quarters of states had made abortion a crime.
The push was not purely medical. Legislators saw criminalization as a way to encourage higher birth rates among certain populations and to reinforce traditional expectations about women’s roles. The new laws also gave physicians a near-monopoly over reproductive decisions: only a doctor could determine whether an abortion was necessary to save a patient’s life, and the overwhelming majority of doctors at the time were men. These prohibitions remained the dominant legal framework for over a century.
Congress and the Comstock Act of 1873
Congress added a federal layer in 1873 by passing the Comstock Act, named after anti-vice crusader Anthony Comstock. The law declared abortion-related items and information “nonmailable matter” and prohibited sending them through the postal system. It covers physical items designed for producing abortion, drugs or instruments advertised for that purpose, and any written material providing information about where or how to obtain one.3Office of the Law Revision Counsel. 18 USC 1461 – Mailing Obscene or Crime-Inciting Matter
For most of the 20th century, courts and federal agencies read the Comstock Act narrowly, and it went largely unenforced against legitimate medical providers. It was never repealed. Its relevance has surged since 2022, with some lawmakers and legal advocates arguing it could be used to ban the mailing of abortion medication nationwide. A 2022 Department of Justice opinion concluded the Comstock provisions apply only to materials intended for unlawful abortions, but that interpretation could be reversed by a future administration.
Roe v. Wade Suspends the State Bans
In 1973, the Supreme Court ruled in Roe v. Wade that the Constitution protects a right to abortion, grounded in the Fourteenth Amendment’s concept of personal liberty. That liberty, the Court held, was “broad enough to encompass a woman’s decision whether or not to terminate her pregnancy.”4Justia Supreme Court Center. Roe v Wade, 410 US 113 (1973) The decision struck down the kind of blanket criminal bans that states had maintained since the 1800s.
Roe created a framework tied to the stages of pregnancy. During roughly the first trimester, the decision belonged to the patient and their doctor. After that point, states could regulate the procedure in ways related to maternal health. After viability, when a fetus could survive outside the womb, states could prohibit abortion entirely except when necessary to preserve the life or health of the mother.4Justia Supreme Court Center. Roe v Wade, 410 US 113 (1973)
In 1992, Planned Parenthood v. Casey replaced Roe’s trimester framework with an “undue burden” test but reaffirmed what the Court called Roe’s “central holding”: states could not prohibit abortion before viability. A state regulation was unconstitutional if its purpose or effect placed a “substantial obstacle in the path of a woman seeking an abortion of a nonviable fetus.”5Justia Supreme Court Center. Planned Parenthood of Southeastern Pa v Casey, 505 US 833 (1992) Together, Roe and Casey kept the 19th-century state criminal bans unenforceable for nearly half a century.
Dobbs and the Supreme Court’s 2022 Reversal
The second wave of criminalization was made possible by the Supreme Court itself. The Dobbs case began with a Mississippi law banning most abortions after 15 weeks of pregnancy, well before viability. The state asked the Court to uphold its law and, ultimately, to overturn Roe and Casey entirely.6Supreme Court of the United States. Dobbs v Jackson Womens Health Organization In June 2022, a 6-3 majority did exactly that.
Justice Samuel Alito wrote the majority opinion. Its core conclusion was blunt: “The Constitution does not confer a right to abortion; Roe and Casey are overruled; and the authority to regulate abortion is returned to the people and their elected representatives.”6Supreme Court of the United States. Dobbs v Jackson Womens Health Organization The majority held that abortion is not a right “deeply rooted in the Nation’s history and tradition,” pointing to the fact that most states treated it as a crime when the Fourteenth Amendment was adopted. Roe, the majority wrote, was “egregiously wrong” from the start, and Casey’s undue burden test had proven unworkable.
To justify overruling nearly 50 years of precedent, the majority walked through five factors: the nature of Roe’s original error, the quality of its legal reasoning, the unworkability of Casey’s standard, the distortion the decisions caused in other areas of law, and the absence of concrete reliance interests that would make reversal unfair.6Supreme Court of the United States. Dobbs v Jackson Womens Health Organization The dissenters warned that the decision abandoned settled expectations.
State Legislatures Move After Dobbs
Dobbs did not itself outlaw abortion. It made state prohibitions enforceable again. Many legislatures had prepared for this moment. Thirteen states had “trigger laws” already on the books, statutes drafted specifically to ban abortion the moment Roe was overturned.7National Conference of State Legislatures. State Abortion Laws Protections and Restrictions Some took effect immediately, others within days or weeks. The result was a rapid geographic split: much of the South and Midwest banned the procedure while the Northeast, West Coast, and several other states preserved or expanded access.
As of early 2026, 13 states maintain total abortion bans, meaning the procedure is prohibited at virtually every stage of pregnancy. Several more states ban abortion at early gestational limits, including six, 12, or 18 weeks. In total, 41 states have some form of restriction in effect, though many of those limits apply only later in pregnancy and align with the kinds of regulations that existed even under Roe.
Exceptions and Who Faces Prosecution
Nearly every state that bans abortion includes some exceptions, but the scope varies widely. The most common categories are threats to the life of the pregnant person, serious risks to physical health, lethal fetal anomalies, and pregnancies resulting from rape or incest. Eight states with bans have no exception for rape or incest at all. Even where exceptions exist on paper, the procedural requirements can be steep, with some states requiring multiple physicians to certify in writing that the exception applies.
State bans target physicians and other providers, not patients. Most states with criminal prohibitions explicitly shield the person who obtains an abortion from prosecution. Penalties for providers range from a few months in prison to the possibility of life imprisonment, depending on the state.7National Conference of State Legislatures. State Abortion Laws Protections and Restrictions Some states also impose civil fines that can reach $100,000 or more per violation, along with permanent revocation of medical licenses.
Private Civil Enforcement
Some states have gone beyond criminal penalties by authorizing private citizens to enforce abortion restrictions through civil lawsuits. The most prominent example created a private cause of action allowing anyone to sue a person they believe helped facilitate an abortion and collect a $10,000 minimum bounty per violation. The mechanism was designed to sidestep constitutional challenges by removing the state itself from enforcement. In response, roughly 18 states and the District of Columbia have passed “shield laws” protecting providers and patients from out-of-state civil and criminal enforcement actions.
Voters as a Counterweight
While state legislatures have driven the post-Dobbs wave of bans, voters have pushed back through ballot measures. Since 2022, multiple states have amended their constitutions to protect abortion rights when the question went directly to voters. California, Michigan, and Vermont passed constitutional amendments in 2022. Ohio followed in 2023. In 2024, voters in Arizona, Colorado, Maryland, Missouri, Montana, and Nevada approved similar measures. Ballot measures in Florida, Nebraska, and South Dakota fell short.
Missouri, which had one of the most restrictive bans in the country, passed a constitutional amendment protecting reproductive freedom by a narrow margin in 2024. The pattern suggests that legislative bans in many states may not reflect majority opinion, and ballot initiatives have become a primary tool for restoring access where legislatures are unlikely to act.
The Short Answer
No single actor made abortion illegal in the United States. The original criminalization came from state legislatures in the second half of the 1800s, driven by an AMA campaign led by physicians like Horatio Storer, with Congress adding the Comstock Act in 1873. Those bans lay dormant under Roe and Casey from 1973 to 2022. The current bans exist because the Supreme Court, in Dobbs, removed the constitutional barrier, and because state legislatures — many with statutes already drafted — moved quickly to enforce or reinstate prohibitions the moment federal protection ended.