What approach to constitutional interpretation best protects liberty? My task in this essay is to answer that modest question. Ultimately, there is no definitive answer that applies to all times and all places. But under the circumstances of the United States for the foreseeable future, originalism is likely to be the best bet. Both the structural and individual rights provisions of the Constitution generally protect liberty more when interpreted from an originalist standpoint than by applying any of originalism’s plausible competitors.
Before even beginning to defend that position, we must first consider what is meant by “liberty.” Adherents of different ideologies have widely differing conceptions. I will focus on the “negative” liberty defended by most libertarians: the right to be free of government interference with one’s economic and personal lives, including the rights to property, contract, speech, religion, and freedom in personal relations. The answer to the question raised by this essay would be very different if we instead focus on left-liberal conceptions of liberty that include an extensive role for welfare state benefits and government regulation.
Even many libertarians—myself included—recognize that negative liberty doesn’t always trump all other values. Proving that a particular theory of constitutional interpretation best promotes liberty does not prove that it is the best overall. A complete theory of constitutional interpretation must also consider other goals such as the provision of public goods and increasing human welfare. A complete theory of judicial review must also address the challenge posed by people who have strong reliance interests vested in incorrect, but firmly established precedents.
Still, negative liberty is an important value—including for many non-libertarians. And the ability to maximize it effectively is an important virtue, even if it is not the only criterion by which theories of constitutional interpretation should be assessed.
Some legal theorists argue that evaluating constitutional theories based on their effectiveness in promoting specific values is inherently illegitimate. The problem with this view is that it divorces constitutional theory from the normative justification for obeying the Constitution (or any legal rule) in the first place. The fact that some people wrote down a set of rules 150 or 200 years ago does not in and of itself create a moral obligation for us to obey them today (or even for their contemporaries to have done so). Neither the Constitution nor any other legal text justifies its own enforcement. If we should obey nonetheless, it must be because of some value or set of values external to the text itself. And the nature of that value is likely to influence the normative decision about what interpretive methodologies should be used to determine the implications of the text for particular cases.
While we may not want judges to rely on their own personal values in applying whatever turns out to be the right theory of constitutional interpretation, the decision of what interpretive theory to use in the first place is not and cannot be a value-neutral enterprise.
Why Not Just Promote Liberty Directly?
Perhaps the real answer to our question is that we should throw out theories of interpretation entirely. Why not just have judges promote liberty directly, by simply deciding each case based on the criterion of what ruling will best maximize liberty in the long run? That approach might sometimes require us to sacrifice some elements of liberty in order to protect others. But it could potentially avoid ever sacrificing liberty for the sake of any other value.
The most obvious objection to this approach is that liberty is not the only value that should be promoted by a system of judicial review. But even from the standpoint of liberty alone, promoting it directly is unlikely to be the best approach under real-world conditions. This paradoxical conclusion holds true for two reasons.
First, to be effective in promoting liberty under realistic conditions, a theory of constitutional interpretation has to gain the assent of judges from a wide range of ideological and partisan backgrounds. Only a small minority of judges are libertarians, and the percentage is likely to increase only slowly. Most non-libertarians are likely to reject a theory of interpretation that directly prioritizes liberty out of hand. By contrast, both originalism and at least some versions of living constitutionalism have a measure of demonstrated cross-ideological appeal. In recent years, the original meaning version of originalism, in particular, has gathered numerous adherents across the political spectrum.
Second, even in a much more libertarian-friendly judiciary, pursuing liberty directly may not achieve the goal as effectively as relying on the results of supermajoritarian decisions embodied in the original Constitution and later amendments. A supermajority process can draw on a much wider range of knowledge and expertise than is available to a handful of Supreme Court justices, or even a larger corps of federal judges. Other things equal, greater and more diverse knowledge is likely to result in rules that better achieve the goal in question. This may not matter if the more knowledgeable decision-makers themselves gave little or no priority to liberty in deciding what constitutional rules to adopt. But, as we shall see, the most important parts of the Constitution were in fact enacted by political movements that placed a high value on liberty, even if not quite as high as that assigned by modern libertarians.
How Originalism Promotes Liberty
It would be foolish to claim that originalism is conducive to liberty under all possible conditions. An originalist approach to enforcing the Constitution of the Soviet Union or the laws of Nazi Germany would likely do far more to undermine liberty than enhance it. More ambiguously, the same may be true of efforts to enforce the original meaning of many contemporary European constitutions that include extensive provisions for welfare rights and grant government wide-ranging powers over economic and social life.
In general, originalism is only likely to promote liberty if the original meaning of the constitution in question protects that value more than the realistically feasible alternatives such as living constitutionalism or deference to the political process. While these conditions do not hold for all constitutions, they do apply to ours.
Start with the original 1787 Constitution. Although it was intended to establish a stronger federal government than existed under the Articles of Confederation, it still imposes tight limits on the scope of federal power. Today, the lion’s share of federal legislation is supposedly authorized by either the Commerce Clause, which gives Congress the power to regulate “Commerce . . . among the several States” or the Spending Clause, which establishes the power to spend money to promote the “general Welfare.”
The original meaning of both is far narrower than modern interpretations. Despite valiant efforts to prove otherwise, the text of the Commerce Clause does not give Congress the power to do more than regulate trade in goods and services across state boundaries and the instrumentalities by which that trade is conducted. It certainly does not give Congress the power to regulate any activity that might have a significant effect on such trade, or on the national economy. As Justice Clarence Thomas and others have pointed out, the modern “effects test” interpretation would make much of the rest of the Constitution superfluous. The Commerce Clause itself also gives Congress the power to regulate trade with foreign nations and with the Indian tribes (which was a much more important part of the economy in 1787 than today). Both of these types of trade clearly have major effects on the economy and on interstate commerce, yet the Founders thought it necessary to grant the power to regulate these types of trade separately.
The same is also true of the Spending Clause. The original meaning of spending for the general welfare likely does not mean what the modern Supreme Court assumes: spending on any object that Congress might consider beneficial. If it did, there would be no reason for the Spending Clause to also grant Congress the power to spend to “pay the debts and provide for the common Defence… of the United States.” Both debt repayment and defense spending plausibly benefit the nation. The true original meaning of General Welfare is most likely captured either by James Madison’s theory that it authorizes Congress to spend money to implement its other enumerated powers, or that it also grants Congress very limited additional authority to spend on objects that really do benefit virtually all Americans. When I teach Constitutional Law I, I often use the example of spending on the destruction of a civilization-threatening asteroid—as in the Bruce Willis action movie Armageddon.
It is sometimes argued that the Necessary and Proper Clause, which gives Congress the power to “make all Laws which shall be necessary and proper for carrying into Execution” other powers granted to the federal government, ends up giving the latter nearly unlimited authority by a kind of back door. But even if we accept the broad interpretation of “necessary” as “useful or convenient” adopted by the Supreme Court in McCulloch v. Maryland (1819), laws authorized by the Clause must be “proper” as well as necessary. And, as I have argued at length elsewhere, the original meaning of “proper” bars assertions of federal authority that give Congress nearly unlimited power or render other enumerated congressional powers superfluous.
Admittedly, the original Constitution imposes mostly structural constraints on federal authority. It carves out only a few individual rights. And it imposes very few constraints of any kind on state governments.
The federalism established by the original Constitution is far from unambiguously beneficial for liberty. State governments often undermine liberty and more expansive federal authority can potentially stop them. The original Constitution’s toleration of state government-imposed slavery is perhaps the most powerful case in point.
But federalism-based limits on congressional power do promote liberty in two important ways. First, decentralization of power limits the likelihood that an oppressive policy will spread to the entire nation, as opposed to affecting only some subset of states. As terrible as slavery and segregation were, they would have been even worse had the federal government enforced them nation-wide (as might have happened had there been a single unitary national policy on these issues in the early republic, or at the height of Jim Crow-era racism). Oppressive state policies affect fewer people than otherwise comparable federal policies.
Second, federalism enables people to “vote with their feet” against oppressive state and local governments, in favor of jurisdictions with better (or at least less bad) policies. Throughout American history, this option has been utilized by oppressed minorities, and people in search of greater freedom and opportunity—including African-Americans, gays and lesbians, and many others. Such foot voting also incentivizes states to cut back on policies that might cause businesses and productive workers to flee.
When the original 1787 Constitution came up for ratification, critics rightly insisted on the need for a Bill of Rights. The Bill of Rights enacted in 1791 contains important protections for a variety of individual liberties, on top of those provided by structural constraints on federal power. Research by Eugene Volokh, Michael McConnell, and other scholars shows that the original meaning of the First Amendment provides much broader protection for freedom of speech and religion than previously thought—including nonpolitical and symbolic speech, and some exercises of religious freedom that go against seemingly “neutral” laws. The original meaning of the Takings Clause of the Fifth Amendment provides strong protection for property rights, including tight “public use” restrictions on the use of what the Founders called the “despotic power” of eminent domain.
As I detail in a forthcoming book, the original meaning of the Public Use Clause would bar not only Kelo v. City of New London (2005), but also Berman v. Parker, the nonoriginalist 1954 decision in which the Supreme Court first held that a “public use” is almost anything the government says it is. Berman opened the door to “blight” and “urban renewal” condemnations that have forcibly displaced millions of people. Originalist scholars on both the right and left now recognize that the original meaning of the Second Amendment provides a robust individual right to bear arms. The original meaning of other parts of the Bill of Rights also often provide greater protection for individual freedom than is available under modern Supreme Court doctrine or many forms of “living Constitution” theory.
Even after the enactment of the Bill of Rights, the original Constitution offered only very limited protection for liberty against the depredations of state governments. As originally envisioned, the Bill of Rights only constrained federal power. Sadly, remedying this defect required a bloody Civil War.
The Reconstruction Amendments enacted in the wake of the war curtailed many of the most serious affronts to liberty permitted by the original Constitution. The Thirteenth Amendment banned slavery, by far the worst such injustice. The Fourteenth Amendment not only restricted racial and ethnic discrimination by the states, but also protects important substantive liberties for all Americans.
There is now a near-consensus among legal scholars of all stripes that the Fourteenth Amendment incorporates all or nearly all of the Bill of Rights against the states. Akhil Amar, Kurt Lash, and others provide strong arguments that that incorporation should be understood to encompass the broader view of many of those rights that predominated in the 1860s, rather than more constricted interpretations of the 1790s.
In addition, although the issue is still disputed, recent scholarship by Randy Barnett, Ryan Williams, Christopher Green, and my George Mason colleague David Bernstein, among others, makes a powerful case that the original meaning of the Due Process and Privileges or Immunities Clauses of the Amendment provide substantial protection for a variety of otherwise unenumerated individual liberties.
This protection extended to a variety of basic traditional rights of free citizens, including both “economic” and “noneconomic” rights. As many of these scholars emphasize, nineteenth century Americans, including those who framed and ratified the Amendment, did not recognize a sharp distinction between the two types of freedoms. Thus, nineteenth and early twentieth century jurisprudence used the Due Process Clause to protect both “economic rights” to freedom of contract in labor relations, and “noneconomic” freedoms, including the right to raise one’s children free of excessive state intervention such as mandates that all children attend public schools and learn only subjects mandated by the state.
The original meaning of these clauses does not provide complete protection for a libertarian conception of freedom. As Bernstein, among others emphasizes, the dominant view at the time would still uphold state regulations that fall within the scope of the “police power” used to promote the health, safety, or welfare of the public. But that still rules out regulations whose primary purpose is to stifle competition for the benefit of favored interest groups, or simply impose the preferences of majority public opinion on dissenting minorities.
Similarly, enforcing the original meaning of the scope of federal power would not completely eliminate federal government policies that infringe on liberty. For example, the original meaning of the Foreign Commerce Clause and the Tax Clause probably gives Congress broad power to enact protectionist legislation restricting the import of foreign goods.
A more complete discussion of the relationship between originalism and liberty would also require consideration of the relevance of different competing versions of originalism, such as original intent and original public meaning.
In my view, what is said above holds true under the form of originalism currently dominant among originalist scholars and jurists: original public meaning originalism, which focuses on the public meaning of the text at the time of enactment. Most of it is also valid under the today less popular original meaning approach, which emphasized the intentions of the individuals who drafted the text. But there are inevitably some divergences between original intent and original meaning, and between different versions to the latter.
Still, this necessarily brief and oversimplified survey of the original meaning of the Constitution shows that it provides strong, if incomplete, protection for individual liberty in a variety of ways. Competing theories must meet a high standard if they are to surpass originalism on this score.
The substantial affinity between originalism and liberty is not accidental. The Founding Fathers and revolutionary generation were heavily influenced by Enlightenment theories of natural rights and political economy that placed a high emphasis on individual liberty, and on property rights.
The emphasis on individual liberty was perhaps even stronger in the case of the Civil War-era Republicans who drafted and ratified the Reconstruction Amendments. They were heavily influenced by the proto-libertarian “free labor” ideology of the antislavery movement, and by a desire to curb infringements on individual liberty enacted by antebellum state governments, especially in the South.
The Living Constitution Alternative
Although originalism offers strong protection for individual liberty, perhaps living constitutionalism can do even better. The range of theoretically feasible living constitution theories is nearly infinite. I cannot categorically exclude the possibility that one of them would protect liberty better than originalism. However, that result is unlikely in the case of those versions of living constitutionalism that currently enjoy widespread support.
Perhaps the best-known version of living constitutionalism is “representation-reinforcement,” the theory—developed by the late John Hart Ely—that judicial review should generally focus on protecting rights necessary for democratic political participation, and helping “discrete and insular minorities” who cannot effectively fend for themselves in the political process. Representation-reinforcement theory can justify strong protection for rights closely related to political participation, such as freedom of political speech and association. It can also protect at least some of the liberties of politically weak minority groups. Depending how broadly the latter concept is interpreted, it could even justify strong judicial enforcement of constitutional rights that are viewed skeptically by conventional left-liberal supporters of the theory. Representation-reinforcement theory is also a valuable counterpoint to claims that strong judicial review necessarily undermines democracy.
But ultimately, the theory offers little protection for a wide range of liberties that are not closely related to political participation, and whose violation may not disproportionately target minorities or the politically weak. It also offers little justification for judicial enforcement of structural limits on government power that are not focused on either enhancing participation or protecting minority groups. In addition, the key concepts of political participation and “discrete and insular minorities” are often frustratingly vague and indeterminate, which leaves a great deal of room for judicial discretion—discretion that can often be used to refuse to enforce liberties that judges are unsympathetic to. For these reasons, representation-reinforcement is unlikely to protect individual liberty as fully as originalism.
Other influential versions of living constitutionalism focus on keeping constitutional interpretation in line with changing social conditions and the views of popular majorities or influential legal elites. For example, “popular constitutionalism” emphasizes the need for judicial interpretations of the Constitution to take account of the views of the general public, particular those embodied in mobilized social movements, such as the civil rights movement or the gun rights movement.
Whatever their other virtues, these types of living constitution theories are unlikely to provide strong, systematic protection for liberties endangered by the political process. Public opinion and influential social movements sometimes favor enhanced protection for liberty; but very often they favor the exact opposite. Moreover, by privileging currently powerful political forces, popular constitutionalism counsels deference to the very entities that are often the greatest threats to liberty. For obvious reasons, freedom is less likely to be endangered by politically weak or disorganized groups than by those that have effectively mobilized themselves and achieved a measure of political influence.
Some influential academic theories of living constitutionalism—most notably Ronald Dworkin’s “chain novel” approach—argue that judges should begin with the constitutional text, but interpret ambiguous phrases to conform with the best available version of liberal political theory, while simultaneously giving some deference to precedent and historic practice. The implications of this approach for liberty depend on your view of the best interpretation of liberal political theory, which – of course – is likely to vary greatly for judges with different values and dispositions. The overall implications for liberty are not likely to be as beneficial as those of originalism, unless the judiciary somehow becomes overwhelmingly libertarian—an unlikely eventuality in the foreseeable future. Moreover, even a strongly libertarian Dworkinian jurist may have difficulty figuring out how to protect liberty as effectively as might be done by following rules enacted by liberty-oriented supermajorities, who may have greater knowledge and insight.
Why Not Leave Liberty to the Political Process?
Among both originalists and living constitutionalists, there are some who prefer judges to largely defer to the political process. If constitutional interpretation raises difficult questions, why not leave them to the elected representatives of the people, except perhaps in cases where the unconstitutionality of their actions is unambiguously clear?
Such judicial deference is unlikely to provide effective protection for liberty. The political branches of government are often the very entities that threaten liberty the most. To defer to their interpretations of the constitutional safeguards meant to constraint their own abuses is much like deferring to wolves’ interpretations of the rules regulating access to chicken coops.
Some advocates of judicial deference hope that if judges defer to the political branches of government, the latter will take constitutional rights more seriously, knowing that they cannot rely on the judiciary as a safety net. History suggests otherwise. When the judiciary largely abdicated enforcement of Fourteenth Amendment protections against racial discrimination in the late 19th century, that helped facilitate rampant Jim Crow laws, not careful legislative reflection on constitutional issues raised by racial discrimination.
A similar pattern emerged when federal judges largely abjured enforcement of constitutional economic liberties, property rights, and structural constraints on congressional power from the 1940s to the 1980s. Violations of these constitutional constraints on government power greatly increased, and most legislators stopped giving them any serious consideration.
It is also dangerous to rely on public opinion as the main protection for constitutional rights. Due to widespread public ignorance, most voters have little knowledge of government policy or of the Constitution. As a result, even constitutional rights that enjoy considerable public support will often be violated with little political backlash, because voters may not even know the violations are occurring. While the most of the public strongly opposes “economic development” takings of the sort that took place in the Kelo case, such condemnations were commonplace for decades, and aroused only modest public opposition until a high-profile Supreme Court case finally broke through the barriers of public ignorance. Public opinion was largely blind to the issue until a dramatic exercise of judicial review caught its attention.
Moreover, survey data show that the public often has a strong bias against individual freedom, particularly on economic issues. On both economic and social issues, support for individual freedom is often closely correlated with political knowledge (when controlling for other variables), and knowledge levels tend to be low. Entrusting liberty to mercies of public opinion is often a dangerous proposition.
Some argue that nondeferential judicial review is antithetical to originalism itself, which supposedly requires deferring to the legislature in all but the most clear cases of unconstitutionality. But, as John McGinnis recently explained on this very site, that view misreads Founding-era understandings of judicial duty, which held that judges should only defer in cases where they could not find the answer to a constitutional question by using standard methods of legal interpretation.
None of this suggests that we should rely on judicial review alone to protect constitutional rights. Far from it. Successful movements to strengthen protection for individual rights have generally relied on a combination of litigation and political action. This formula worked for the civil rights movement and the women’s rights movement. In recent years, it has achieved notable breakthroughs for gay rights, for opponents of state-sponsored racial preferences, and for advocates of constitutional property rights and the right to bear arms.
Reliance on litigation and judicial review is just one part of a broader strategy for enhancing freedom; others include conventional political mobilization, and influencing elite intellectuals and policymakers. Efforts to protect liberty by relying on judicial review alone are likely doomed to failure. But it would also be a serious mistake to abjure this important tool.
Although originalism provides greater protection for individual liberty than other realistically feasible approaches to constitutional interpretation, it still has its limits. At this late date, the judiciary cannot fully restore the original meaning of the Constitution in the face of longstanding adverse precedent and government policy. Attempting to do so would create a political backlash that is likely to undermine both liberty and the institution of judicial review itself. It could also undermine prospects for stronger enforcement of the original meaning itself. Prudent originalist jurists can use judicial review to move us closer to the original meaning, but are unlikely to be able to get all the way there—at least not for a long time to come, if ever.
Moreover, as I emphasized at the start, liberty is not the only value that must be considered in evaluating theories of constitutional interpretation. Even if originalism is the best realistic alternative for purposes of protecting liberty, that doesn’t necessarily make it the best theory overall.
Despite these caveats, the relatively close affinity between originalism and liberty is an important consideration in evaluating competing approaches to constitutional theory. It has obvious significance for libertarians. But it should also matter to others who consider negative liberty an important value, even if they are often more willing than libertarians to subordinate it to other goals.
 Spending on Willis’ mission to destroy the asteroid does not come under the heading of defense spending, because it is not a response to an attack by a conscious enemy who deliberately intends to do us harm.
 See Ilya Somin, “The Individual Mandate and the Proper Meaning of ‘Proper,’” in The Health Care Case: The Supreme Court’s Decision and Its Implications (Nathaniel Persily, Gillian Metzger, and Trevor Morrison, eds., Oxford University Press, 2013).
 I discuss federalism and its relationship to liberty in greater detail in Ilya Somin, “Libertarianism and Federalism,” Cato Institute Policy Analysis No. 751, June 30, 2014, available at http://www.cato.org/publications/policy-analysis/libertarianism-federalism
 Ilya Somin, The Grasping Hand: Kelo v. City of New London and the Limits of Eminent Domain, (Chicago: University of Chicago Press, 2015), ch. 2.
 See David E. Bernstein, Rehabilitating Lochner: Defending Individual Rights Against Progressive Reform, (Chicago: University of Chicago Press, 2011).
 I discuss the different versions of originalism in far more depth in Ilya Somin, “Originalism and Political Ignorance,” 97 Minnesota Law Review 625 (2012).
 On property rights, see, e.g., James W. Ely, Jr., The Guardian of Every Other Right: A Constitutional History of Property Rights (New York: Oxford University Press, rev. ed. 2008); on the role of Enlightenment versions of individual liberty, see, e.g., Gordon S. Wood, The Radicalism of the American Revolution (New York: Vintage, 1993).
 John Hart Ely, Democracy and Distrust: A Theory of Judicial Review (Cambridge: Harvard University Press, 1980).
 For example, I have argued that it justifies strong enforcement of public use constraints on takings, because blight and economic development condemnations disproportionately victimize politically weak minority groups. See Somin, Grasping Hand, ch. 3.
 See, e.g., Ronald Dworkin, Law’s Empire (Cambridge: Harvard University Press, 1986).
 I review the depressing evidence on political ignorance in Somin, Democracy and Political Ignorance: Why Smaller Government is Smarter (Stanford: Stanford University Press, 2013).
 Even then, many state legislatures were able to exploit public ignorance about the details of law by passing cosmetic reforms that only pretended to impose constraints on such uses of eminent domain. See Somin, Grasping Hand, chs. 5-6.
 See, e.g., Scott Althaus, Collective Preferences in Democratic Politics (Cambridge: Cambridge University Press, 2003); Bryan Caplan, The Myth of the Rational Voter (Princeton: Princeton University Press, 2007).
 See John McGinnis, “Why Thayer is Clearly Mistaken About Judicial Restraint,” Liberty Law Blog, Mar. 20, 2015, available at http://www.libertylawsite.org/2015/03/20/why-thayer-is-clearly-mistaken-about-judicial-restraint/. As McGinnis puts it, “for the Framers’ generation the meaning of an unclear text could be discovered or largely elucidated by legal methods.”