Most Americans, asked whether child marriage is legal in the United States, will guess no. They are wrong about most of the country. As of 2024, fewer than half of U.S. states had set eighteen as the absolute minimum marriage age. The rest allow marriage below eighteen with some combination of parental consent, judicial approval, or pregnancy exceptions. In a handful of states until very recently there was no statutory floor at all - marriages of twelve-year-olds and ten-year-olds appear in the public record.

Fraidy Reiss, an Orthodox Jewish woman forced into marriage at nineteen who eventually escaped and built the advocacy organization Unchained At Last, has done more than any single person to document the scale and push the legal reform. Her organization's data, drawn from state marriage records, shows roughly 300,000 minors married in the United States between 2000 and 2018. The overwhelming majority were girls. The overwhelming majority of the spouses were adult men. The age gaps were often substantial - marriages of fifteen-year-old girls to men in their thirties and forties are not anomalies but recurring entries in the data.

Law 5 - Revise - is the obvious frame, but the U.S. case is interesting because it shows how a society can sign international commitments, claim to be a leader on women's and children's rights, and simultaneously fail to revise a basic feature of its domestic legal architecture. The reasons are structural and political. Family law in the U.S. is state law, which means reform proceeds one legislature at a time. The coalitions opposing reform include some religious-liberty advocates worried about precedent, some parental-rights advocates suspicious of the state's authority over family decisions, and some legislators concerned about pregnant minors who, they argue, should be able to marry the fathers of their children.

Each of these objections collapses on inspection. Religious liberty does not require the state to issue marriage licenses to children; religious communities are free to bless whatever they want, but the civil contract is the state's. Parental rights do not include the right to transfer a child into a sexual and economic contract she cannot exit on her own. The pregnant-minor argument inverts the actual data, which shows that marriage worsens outcomes for pregnant adolescents rather than improving them - the marriages have higher rates of subsequent abuse and divorce, and the economic situation gets worse, not better.

The fight has been won state by state since roughly 2018. Delaware and New Jersey were the first to set eighteen as the absolute floor with no exceptions. Pennsylvania, Minnesota, Rhode Island, New York, Massachusetts, Vermont, Connecticut, Michigan, Washington, and several others followed. The pattern is geographic but not strictly partisan - the states that have reformed include red, blue, and purple jurisdictions, suggesting the issue can find majorities when the data is presented and the loopholes are explained. The states that have not yet reformed include large parts of the South and Mountain West, where opposition has been more organized.

The fight is also a useful case study in how a policy reform with no organized opposition (no industry depends on child marriage, no significant lobby advocates for it) can still take decades to win. The obstacle is not opposition; it is inertia, lack of awareness, and the legislative bandwidth problem. Most state legislators, asked privately, will support a minimum-age law without exceptions. The bills die in committee or on the calendar, not on the floor. Reiss and Unchained At Last have produced model legislation, traveled to dozens of state capitals, and built coalitions with survivors, medical associations, and child welfare groups. The work is unglamorous and effective.

Naomi Cahn and June Carbone's family law scholarship has tracked the broader pattern of which kinds of family-law reform succeed and which stall in the U.S. legal landscape. They identify a "red family / blue family" divide that does not map cleanly onto child marriage but illuminates why the issue does not become a culture-war flashpoint. Both sides of the political spectrum can find reasons to support reform once the facts are clear, which is why progress, though slow, has been steadier than on more polarized family issues.

The remaining task is finishing the map. Roughly thirty states still permit some form of child marriage as of 2024. The federal government has limited authority to compel state action, though it could condition federal funding on minimum-age compliance. The Marriage Without Consent Act and similar proposals have been introduced and not passed. Until the map is finished, U.S. child marriage will continue at the rate of several thousand per year - small relative to the global total, but morally significant as the gap between what the country claims about itself and what its statutes permit.