What is the Ninth Amendment?

The Ninth Amendment reads in full: 'The enumeration in the Constitution, of certain rights, shall not be construed to deny or disparage others retained by the people.' Ratified December 15, 1791 as part of the Bill of Rights, the Ninth Amendment was James Madison's answer to a specific objection raised during the ratification debates about the Constitution. Alexander Hamilton argued in Federalist No. 84 that a Bill of Rights was not only unnecessary but dangerous: by listing specific rights, the implication might follow that the federal government had authority to do anything not covered by an explicit prohibition. If the freedom of the press were guaranteed, some might argue, the government would have power over every other form of expression. Madison accepted the force of this argument but concluded that a Bill of Rights was politically necessary to secure ratification in Virginia and elsewhere. His solution was to add the Ninth Amendment as an express rule of construction -- a provision that the enumerated rights were not intended to be a complete list and that identifying some rights for explicit protection did not extinguish or diminish all others. At the Virginia ratifying convention in 1788, Anti-Federalist objectors including Patrick Henry and George Mason demanded a bill of rights as a condition of their states' ratification; the Ninth Amendment addressed the textual problem their demand created without conceding the Federalist argument about the dangers of enumeration.

The Ninth Amendment remained largely dormant as a basis for constitutional litigation throughout most of American history. Courts occasionally acknowledged its existence but declined to use it as an independent basis for invalidating legislation. The prevailing view was that the Amendment stated a rule of interpretive construction -- it told courts and government officials not to read the absence of a right from the constitutional text as proof that the government could override it -- but did not itself identify or create specific enforceable rights that judges could apply in particular cases. In the nineteenth and early twentieth centuries, courts that recognized rights beyond those explicitly enumerated typically derived them from the Due Process Clause of the Fifth Amendment (against federal action) or, after ratification of the Fourteenth Amendment in 1868, from the Due Process Clause of the Fourteenth Amendment (against state action). The doctrine of substantive due process -- the principle that the Due Process Clause protects certain fundamental liberty interests from government interference regardless of procedural regularity -- became the primary vehicle for recognizing unenumerated rights at the federal constitutional level, largely bypassing the Ninth Amendment as a freestanding source of authority.

The Supreme Court's most prominent invocation of the Ninth Amendment came in Griswold v. Connecticut, 381 U.S. 479 (1965), which invalidated a Connecticut statute making it a crime for any person to use contraceptives or to assist another in doing so, as applied to a physician and the executive director of the Planned Parenthood League of Connecticut who were prosecuted for providing contraceptive advice to married persons. Justice William O. Douglas wrote for the majority of the Court, finding a constitutional right to marital privacy in the 'penumbras formed by emanations' from specific Bill of Rights guarantees -- the First Amendment's right of association, the Third Amendment's protection against quartering soldiers, the Fourth Amendment's right against unreasonable searches and seizures, the Fifth Amendment's self-incrimination protection, and the Ninth Amendment itself. Justice Arthur Goldberg wrote a concurrence joined by Chief Justice Earl Warren and Justice William Brennan that provided the most direct engagement with the Ninth Amendment in the Court's history: Goldberg argued that the Ninth Amendment's text and history demonstrated that the Framers believed there are additional fundamental rights, protected from governmental infringement, which exist alongside those fundamental rights specifically mentioned in the first eight constitutional amendments. Goldberg emphasized that the Ninth Amendment showed the Framers did not intend the Bill of Rights to be an exhaustive catalogue of every right retained by the people. Justice John Marshall Harlan II concurred in the judgment separately, relying instead on the liberty interest protected by the Due Process Clause of the Fourteenth Amendment. Justices Hugo Black and Potter Stewart dissented, with Black rejecting both the penumbras theory and the Goldberg concurrence's reading of the Ninth Amendment: he argued that the Amendment was not an independent source of substantive rights that judges could enforce and that the majority was substituting its own policy preferences for legislative judgment.

The Griswold right to privacy was subsequently applied in Eisenstadt v. Baird, 405 U.S. 438 (1972), which extended the right to contraception to unmarried persons, and in Roe v. Wade, 410 U.S. 113 (1973), which recognized a constitutional right to abortion. Justice Harry Blackmun's majority opinion in Roe rested the right on the liberty interest protected by the Due Process Clause of the Fourteenth Amendment -- following Justice Harlan's approach in Griswold -- rather than on the Ninth Amendment directly. The Roe framework was substantially modified in Planned Parenthood of Southeastern Pennsylvania v. Casey, 505 U.S. 833 (1992), in which a joint opinion by Justices O'Connor, Kennedy, and Souter (joined in relevant parts by Justices Blackmun and Stevens) reaffirmed what it called the 'essential holding' of Roe under the 14th Amendment's Due Process Clause while replacing the trimester framework with the undue burden standard. Lawrence v. Texas, 539 U.S. 558 (2003), relied on the 14th Amendment's Due Process Clause to strike a Texas statute criminalizing same-sex intimate conduct, and Obergefell v. Hodges, 576 U.S. 644 (2015), held 5-4 in an opinion by Justice Kennedy that the 14th Amendment requires states to license and recognize same-sex marriages. In each of these decisions, the Court grounded the protected liberty interest in the Due Process Clause of the Fourteenth Amendment rather than in the Ninth Amendment as a freestanding source of rights.

Dobbs v. Jackson Women's Health Organization, 597 U.S. 215 (2022), overruled Roe and Casey, holding that the Constitution does not confer a right to abortion and returning the question of abortion regulation to the individual states. Justice Samuel Alito wrote for the majority, which held that a right to abortion is not deeply rooted in the nation's history and tradition and is not implicit in the concept of ordered liberty -- the standard the Court applies to determine whether a liberty interest is protected by the Fourteenth Amendment's Due Process Clause. Justice Clarence Thomas concurred in full and wrote separately to urge the Court to reconsider other precedents that had recognized unenumerated rights under the 14th Amendment's Due Process Clause, including Griswold (contraception), Lawrence (same-sex intimacy), and Obergefell (same-sex marriage), arguing that they too should be reconsidered in appropriate future cases. The majority opinion expressly distinguished those precedents, stating that the Dobbs decision concerns only abortion. Justice Stephen Breyer, joined by Justices Sotomayor and Kagan, dissented. Following Dobbs, the constitutional protection of unenumerated rights more generally -- and the role of the Ninth Amendment in that analysis -- remains an area of active scholarly and legal debate about what protections the Constitution provides for rights not explicitly listed in its text.

The central interpretive dispute about the Ninth Amendment has two principal positions in academic and judicial discourse. The first position, associated with Justice Black's dissent in Griswold and Justice Scalia's general skepticism of unenumerated rights, treats the Amendment as purely a rule of construction: it prevents courts from inferring that the government has unlimited power over matters not covered by a specific enumerated right, but it does not itself identify or authorize judicial enforcement of particular substantive rights. On this view, the task of identifying and protecting rights not listed in the Constitution belongs to the democratic process through legislation rather than to courts through constitutional adjudication. The second position, associated with Justice Goldberg's Griswold concurrence and elaborated by scholars including Professor Randy Barnett, treats the Ninth Amendment as textual authorization for courts to identify and protect a category of fundamental unenumerated rights retained by the people -- rights that predated the Constitution and that the Framers understood to be preserved even without explicit constitutional statement. For the 2028 presidential election, the Ninth Amendment is relevant to ongoing debates about the constitutional status of reproductive rights after Dobbs, the scope of privacy interests in an era of digital surveillance and data collection, and the general question of what the Constitution protects beyond its explicit enumerated guarantees. The 2028 winner will appoint federal judges -- potentially including Supreme Court Justices -- who will apply these competing interpretive frameworks to cases involving unenumerated rights for the next generation.