During the much-publicized Senate hearings on his nomination to the U.S. Supreme Court in 1987, Judge Robert Bork famously analogized the Ninth Amendment to a constitutional “inkblot,” arguing that judges could not use the amendment to decide cases “without knowing something of what it means.” Judge Bork’s inkblot analogy provoked a wave of criticism from self-described “noninterpretivists,” who argued that the Ninth Amendment’s recognition of unenumerated “rights retained by the people” demonstrated the Founders’ rejection of Bork’s jurisprudential approach.

This controversy also inspired a number of originalist scholars to undertake their own historical investigations to provide a more satisfactory answer to the question of how originalist judges should go about interpreting and applying the Ninth Amendment. These investigations have uncovered a wealth of information regarding the circumstances that led to the amendment’s inclusion in the Bill of Rights and the specific concerns it was designed to address. But these impressive historical excavations have not led to a consensus view among originalists regarding the amendment’s proper interpretation. Instead, there are presently three very different originalist theories of the Ninth Amendment’s original meaning and modern significance.

Before discussing the leading originalist theories of the Ninth Amendment, it will be useful to briefly summarize the circumstances that led to its inclusion in the Bill of Rights. The story of the Ninth Amendment’s adoption begins with the decision by the Philadelphia convention to omit a bill of rights from the original Constitution of 1787. The absence of a bill of rights was among the most controversial features of the original constitutional design and provided a rallying point for Anti-Federalist opposition during the state ratification debates. Supporters of ratification quickly converged on a defense of the decision to omit a bill of rights that was first articulated by Philadelphia Framer James Wilson. Wilson defended the Framers’ decision to leave even very popular rights, such as freedom of the press, unprotected because the “very declaration” of such a right in the Constitution “might have been construed to imply that some degree of power was given” to the federal government with respect to the press “since we undertook to define its extent.”

Wilson’s argument drew upon the interpretive canon inclusio unius est exclusio alterius (the inclusion of one thing necessarily excludes all others), which was widely accepted by courts at the time. Federalists in other states quickly rallied to Wilson’s argument, contending that if a bill of rights had been included in the Constitution, courts might construe the limited enumeration of rights to deny the existence of other rights and to constructively enlarge the scope of federal powers. As Alexander Hamilton warned in The Federalist No. 84, a bill of rights that “contain[ed] various exceptions to powers which are not granted” would “afford a colorable pretext to claim more than were granted.” Instead of relying on a limited and almost certainly incomplete enumeration of particular rights that the people would retain after the Constitution’s adoption, Federalists argued that such rights would be better protected by the limited enumeration of federal powers.

But this defense of the Philadelphia convention’s decision to omit a bill of rights left Federalists open to a devastating rejoinder. Because the Constitution that emerged from Philadelphia already protected a very limited set of rights, including the right of habeas corpus and the right to trial by jury in criminal cases, Anti-Federalists argued that the Constitution already posed the threat of expansive interpretation that Federalists claimed would result from enumerating rights. Federalists never settled on a satisfactory response to this objection. Nonetheless, ratification in the states proceeded apace, though increasingly supported by a tacit understanding that additional rights would be constitutionally protected through the Article V amendment process following ratification.

Several state ratifying conventions proposed lists of amendments that they wished to see adopted following ratification. Although none of these proposals perfectly mirrored the language that was ultimately included in the Ninth Amendment, two sets of such proposed amendments have been identified by modern originalists as potentially relevant to the amendment’s original meaning. The first set of proposals called for an amendment that would expressly recognize the existence of “retained” individual natural rights. A characteristic example of such a proposal, suggested by Virginia’s ratifying convention, acknowledged the existence of “certain natural rights, of which men, when they form a social compact, cannot deprive or divest their posterity,” including “the enjoyment of life and liberty, with the means of acquiring, possessing, and protecting property, and pursuing and obtaining happiness and safety.” The second set of amendment proposals, which were targeted more directly at the Federalists’ concerns regarding the inclusio unius canon, called for a rule of construction providing that provisions expressly withholding particular powers from Congress should not be read to imply the existence of unenumerated federal powers.

Following ratification, James Madison became the leading champion of a federal bill of rights as a representative from Virginia in the First Congress. Madison synthesized several of the state ratifying conventions’ proposals into a list of proposed amendments that provided an important template for the first ten amendments to the Constitution. One of Madison’s proposed amendments, which eventually evolved into the current Ninth Amendment, combined aspects of both the “retained” natural rights provisions proposed by various state conventions and the separate set of proposals calling for an interpretive rule prohibiting the constructive enlargement of federal powers. Madison’s proposal declared that “exceptions” of constitutional powers “made in favor of particular rights” should “not be so construed as to diminish the just importance of other rights retained by the people, or as to enlarge the powers delegated by the Constitution. . . .”

In a speech introducing the proposed amendments in the House, Madison explained the significance of this provision in the following terms:

It has been objected . . . against a bill of rights, that, by enumerating particular exceptions to the grant of power, it would disparage those rights which were not placed in that enumeration, and it might follow by implication, that those rights which were not singled out, were intended to be assigned into the hands of the general government, and were consequently insecure. This is one of the most plausible arguments I have ever heard urged against the admission of a bill of rights into this system; but, I conceive, that it may be guarded against.

Madison specifically identified his proto– Ninth Amendment as reflecting his effort to guard against such arguments.

Following this speech, Madison’s proposals were referred to a Select Committee of the House on which he served. Unfortunately, this Select Committee kept no formal record of its proceedings, leaving modern interpreters with limited information regarding the considerations that influenced the amendment’s final wording. A possible clue to the Select Committee’s internal deliberations is provided by a handwritten list of proposed amendments penned by one of its members, Roger Sherman of Connecticut. The second amendment listed on the Sherman draft declared that “[t]he people have certain natural rights which are retained by them when they enter into Society,” including “rights of Conscience in matters of religion,” “of acquiring property and of pursuing happiness & Safety” and “of Speaking, writing and publishing their Sentiments,” and barring the federal government from “depriv[ing]” them of such rights. A separate amendment in the Sherman draft contains a somewhat garbled provision that bears some resemblance to the rule-of-construction proposals urged by several of the state ratifying conventions: “nor shall . . . the exercise of power by the Government of the united States particular instances here in enumerated by way of caution be construed to imply the contrary.”

In the end, the Select Committee settled on new language that departed from both Madison’s initial proposal and the language reflected in the Sherman draft. This new language closely tracked the language that ultimately was included in the Ninth Amendment. For reasons that are not known, the reference to constructive enlargement of federal powers, which had appeared in both Madison’s initial proposal and in proposals submitted by the state ratifying conventions, was dropped from the final version, limiting the Ninth Amendment’s rule of construction to a prohibition on “constru[ing]” the “enumeration in the Constitution of certain rights to deny or disparage others retained by the people.”

In considering the disagreement among modern originalists regarding the Ninth Amendment’s original meaning, it is useful to note a distinction between what the amendment says explicitly and what might be implied by or inferred from its reference to other rights “retained by the people.” When read literally, the only thing the Ninth Amendment does is state a rule about how other provisions in the Constitution should be read. The Ninth Amendment thus stands as one of only a handful of provisions, along with the Eleventh Amendment and Article IV, Section 3, Clause 2, that speak to how the Constitution itself should be interpreted. The Ninth Amendment’s explicit command does not directly confer rights or limit the scope of federal powers. Rather, the Amendment simply instructs interpreters to reject arguments that seek to use the existence of particular enumerated rights in the Constitution to “deny or disparage” other “retained” rights.

This rule of construction function is at the center of the traditional originalist view of the Ninth Amendment; it views the amendment as a direct response to the inclusio unius concerns expressed during the ratification debates of 1787 and 1788. This traditional view was defended by Justice Hugo Black in his dissenting opinion in Griswold v. Connecticut (1965): quoting Madison’s Bill of Rights speech, Black described the Ninth Amendment as having been “intended to protect against the idea that ‘by enumerating particular exceptions to the grant of power’ to the Federal Government ‘those rights which were not singled out, were intended to be assigned into the hands of the General Government. . . . ’”

Proponents of this traditional view have expressed subtly different understandings of what the Ninth Amendment’s “retained rights” language was originally understood to encompass. But they agree that its prohibition on “denying or disparaging” such retained rights only comes into play when the basis for denial or disparagement is premised on the fact that the Constitution contains an enumeration of rights. Proponents of this view further agree that the amendment’s interpretive command does not raise the “retained” rights referred to in the amendment to the status of constitutional rights and does not directly authorize courts to invalidate laws that infringe upon such rights. Instead, such “retained” rights are simply left with whatever legal status they would have possessed if an enumeration of rights had not been included in the Constitution. The traditional view thus interprets the Ninth Amendment as a “hold harmless” provision that functions much like the similarly phrased provision in Article IV instructing that the Constitution should not be “so construed as to Prejudice any Claims of the United States, or of any particular State.”

While the traditional view is supported by a number of originalist scholars, this understanding of the provision has been called into question by two broader originalist theories. Though each of these competing theories recognizes the amendment’s function as a rule of construction, both argue that a normal speaker of English at the time of enactment would have understood the amendment’s text as implying both that the “retained” rights it refers to actually exist and that the federal government is prohibited from “denying or disparaging” those rights. Thus, according to these theories, the Ninth Amendment’s original meaning (including both its explicit meaning and the implications that would have been understood by an ordinary reader) prohibits all denial or disparagement of “retained rights,” even if such denial or disparagement is not premised on the misconstruction of some enumerated right.

The first of these competing theories is closely associated with the work of Randy Barnett. Much like the “noninterpretivists” of earlier decades, Barnett argues that the Ninth Amendment’s reference to “retained” rights refers to unenumerated individual rights and that the amendment should be construed to empower courts to enforce such rights directly in the same manner as enumerated rights. But unlike those nonoriginalists who view the Amendment as an open-ended invitation for judges to protect only those unenumerated rights they find appealing, Barnett argues that the amendment’s retained rights language points to a historically defined standard. According to Barnett, the “retained” rights to which the Ninth Amendment refers are individual natural rights that individuals possessed before the Constitution’s adoption and that they “retained” to themselves upon forming their government. Barnett draws support for this interpretation from a variety of sources, including the natural rights language contained in Roger Sherman’s draft bill of rights, early American legal treatises, and Madison’s public statements regarding the amendment, as well as Madison’s private, handwritten notes for his bill of rights speech. Barnett contends that the “retained” natural rights to which the amendment refers may be protected by adopting a judicially enforced “presumption of liberty” that would require the federal government to demonstrate that its regulations are truly necessary to protect the liberties of others and not merely a pretense to impose undue burdens on the rightful exercise of natural rights by individuals.

More recently, Kurt Lash has defended a competing originalist interpretation of the Ninth Amendment that is distinct from both the traditional view and Barnett’s individual natural rights interpretation. Lash emphasizes the similarity between the Ninth Amendment and the calls from numerous state ratifying conventions for a rule of construction that would limit the constructive enlargement of federal powers. Lash acknowledges the linguistic distinction between the states’ rule-of-construction proposals and the final text of the Ninth Amendment, but argues that the Ninth Amendment’s focus on preserving retained rights is properly viewed as responding to the state ratifying conventions’ focus on constraining federal power. Lash argues that the amendment’s reference to “retained rights” is best understood as encompassing both individual natural rights and the peoples’ collective right to local self government within their respective states. Like Barnett, Lash views the Ninth Amendment’s textual recognition of other retained rights as supporting judicial protection of such rights even in situations where the danger to such rights does not arise from arguments premised on the fact that other rights have been enumerated. But unlike Barnett, Lash sees the primary significance of the Ninth Amendment as a limitation on federal interference with collective self-governance in the states.

One point on which proponents of all three of the principal originalist theories regarding the Ninth Amendment tend to agree is that the amendment, like other provisions of the Bill of Rights, was originally designed to limit the power of the federal government alone and not that of the states. Thus, for example, under Barnett’s individual natural rights interpretation, the amendment prohibits the federal government from infringing individual natural rights but does not impose any similar restriction on the states. An important corollary of this limitation is that the Ninth Amendment confers no power on the federal government, including the federal courts, to protect individual natural rights against state infringement. If any such power exists, it must be found in some other source, such as the Fourteenth Amendment’s Privileges or Immunities Clause.

The scholarly attention lavished on the Ninth Amendment in recent decades has not been matched by a similar level of interest in the amendment among the judiciary. When it comes to Supreme Court decisions, it is much easier to identify instances where the potential interpretive significance of the Ninth Amendment was overlooked than it is to find instances where the amendment exerted a clear influence on the Court’s ultimate decision. For example, Justice Samuel Chase’s well-known paean to unwritten constitutionalism in Calder v. Bull (1798) contained no mention of the Ninth Amendment or that amendment’s suggestion that non-enumerated rights had been “retained” by the American people. Likewise, Chief Justice Marshall’s famous opinions in McCulloch v. Maryland (1819) and Gibbons v. Ogden (1824) made no effort to grapple with the possible tension between the expansive interpretations of federal power articulated in those cases and the Ninth Amendment’s possible role as a limit on constructive enlargement of federal powers. And in The Legal Tender Cases (1871), the Court seemed to validate the worst fears of Wilson and other Federalists regarding the misapplication of the inclusio unius canon by asserting that the inclusion of a Bill of Rights in the Constitution “tend[ed] plainly to show” that the enactors expected the federal government would possess unenumerated powers. The Ninth Amendment, which had been adopted for the specific purpose of guarding against such reasoning, went unmentioned by the Court.

The earliest mention of the Ninth Amendment in a Supreme Court opinion came in Justice Joseph Story’s dissent in Houston v. Moore (1820), where Story associated the amendment primarily with limiting the constructive enlargement of federal powers. This was by far the predominant judicial application of the amendment throughout the nineteenth century and the early portion of the twentieth century. Following the New Deal expansion of federal regulatory power, this interpretation faded in significance, and the Ninth Amendment largely fell into judicial disuse.

Justice Arthur Goldberg’s concurring opinion in Griswold in 1965 signaled a possible revival of judicial interest in the Ninth Amendment. In that opinion, Goldberg pointed to the amendment as “reveal[ing] that the Framers of the Constitution believed that there are additional fundamental rights, protected from governmental infringement, which exist alongside those fundamental rights specifically mentioned in the first eight constitutional amendments” and as supporting the Court’s decision to strike down state laws that infringed the unenumerated right to marital privacy. But Goldberg’s suggestion that a jurisprudence of unenumerated rights be grounded in the Ninth Amendment went unheeded. Justice William Douglas’s majority opinion in Griswold briefly mentioned the Ninth Amendment as part of a laundry list of textually specified individual rights, the “emanations” from which formed “penumbras” that allowed the Court to infer the existence of an unenumerated right to privacy.

In subsequent unenumerated rights cases like Roe v. Wade (1973), Planned Parenthood of Southeastern Pennsylvania v. Casey (1992), and Lawrence v. Texas (2003), the Court has moved away from this type of “penumbral” reasoning, as well as the Ninth Amendment, preferring instead to ground its fundamental rights jurisprudence in the “substantive” dimensions of the Fifth and Fourteenth Amendments’ Due Process Clauses. The Supreme Court has never held the Ninth Amendment to be incorporated against the states through the Fourteenth Amendment, making it one of only a handful of Bill of Rights provisions that have not been so incorporated.