We live in an age of extreme political polarization. That polarization runs so deep that we are even divided over how to interpret the Constitution. Conservatives insist that originalism — which seeks the meaning of the Constitution as it was understood when it was written — is the only legitimate approach. Liberals reject originalism as rule by the dead hand of the past and contend that judges should instead seek the meaning of a “living constitution,” one that keeps pace with contemporary conditions and values. Worse, the two sides accuse each other of arguing in bad faith — and subverting the genuine rule of law — by using their preferred method of constitutional interpretation as mere rhetorical cover for simply getting the political outcomes that they want.

It need hardly be said that such polarization is alarming. The country is divided enough without being divided over how to interpret our fundamental law, which ought to be one of our strongest bonds of political unity. Accordingly, it is the duty of intelligent and public-spirited citizens to seek a way out of this polarization, to find, if possible, some common ground regarding constitutional interpretation.

Cass Sunstein’s new book, How to Interpret the Constitution, can be understood as a contribution to this important effort. Sunstein, a professor at Harvard Law School, tries to establish a framework in which citizens can disagree reasonably and constructively about theories of constitutional interpretation. The first step toward reasonable disagreement is for all sides to acknowledge that none of them is “right” in any absolute sense. According to Sunstein, none of the contending theories can claim to be the only correct or permissible one. Therefore, he suggests, the only way to judge them is by a kind of moral pragmatism. We must ask about each theory of interpretation whether it, on the whole, makes our system of constitutional law “better” rather than “worse.”

Sunstein develops this argument by drawing on the work of political theorist John Rawls. We all bring certain “fixed points” — convictions about which cases must have been correctly decided or what principles must be vindicated — to our thinking about constitutional law. We must accordingly evaluate the competing theories of interpretation against these fixed points. For example, a modern American liberal might well regard Obergefell v. Hodges (2015) — the case that established a constitutional right to same-sex marriage — as a fixed point. Such a liberal would accordingly be inclined to reject any theory of interpretation that could not recognize the legitimacy of the Obergefell decision. Of course, the liberal, like anybody else, will have many other “fixed points” that must be consulted in seeking a theory of interpretation. Therefore, we must also try to achieve a Rawlsian “reflective equilibrium,” or a state in which our various judgments are in “alignment.” In other words, consulting our various fixed points, we must seek a theory of constitutional interpretation that is as coherent as we can make it and that, overall, makes our constitutional system “better” instead of “worse.”

Establishing these rules of engagement is Sunstein’s primary purpose. But he also takes the opportunity to present his own fixed points and his own preferred approach to constitutional interpretation. Not surprisingly, Sunstein’s fixed points largely overlap with the moral and political convictions of a liberal who came of age in the late 20th century and who wishes to keep up with and affirm the “progressive” developments of the early 21st century. For him, the landmark liberal Supreme Court rulings of the last several decades are to be preserved, and any theory of interpretation that threatens them is suspect. In addition, Sunstein holds that a good theory of interpretation will recognize that the meaning of the Constitution can change over time because of changes in social values. Sunstein endorses this idea because it opens the door to future progressive developments in American constitutionalism — such as the discovery of new rights that will have to be incorporated into our fundamental law.

Sunstein’s book has two strengths. First, he provides a lucid and largely evenhanded account of the various theories of constitutional interpretation that contend for primacy in our discourse. We are introduced to originalism in its various forms, to “traditionalism” (informed by the thought of Edmund Burke), to Thayerism (based on James Bradley Thayer’s arguments for judicial restraint), to the democracy-promoting jurisprudence of John Hart Ely, to the “moral reading” of the Constitution defended by Ronald Dworkin, to the incrementalism of common-law constitutionalism, and to the more recent “common-good constitutionalism” popularized by Adrian Vermeule. This overview is valuable, especially for the nonexpert audience to which Sunstein’s book is addressed. Second, Sunstein’s approach is in some ways well adapted to lessen the polarization with which we are faced. He writes in a non-polemical and even amiable tone, admitting the strengths and weaknesses of the various alternatives, striving to be fair even to the ones he disapproves.

How to Interpret the Constitution, however, fails in its main purposes. In order to defend his pragmatic approach to judging among the competing theories, Sunstein must try to refute the principled arguments in favor of originalism — arguments that originalism is the “right” or “correct” approach to constitutional interpretation. One of these arguments holds that originalism is essential to a real interpretation of any text. After all, if we are trying to interpret, say, Hamlet, we will try to find out what Shakespeare meant by the terms he chose to use in that work. Sunstein, however, denies that there is such a thing as a true nature of interpretation, or such a thing that interpretation simply “is.”

His denials are unconvincing. He acknowledges that originalism is how we tend to approach ordinary communication. We want to know what the speaker meant by the words used. He further admits that seeking the original meaning of a communication makes sense in the context of a “hierarchical organization.” When given instructions by a superior, we try to understand what that superior intended us to do. Sunstein insists that legal interpretation is different. He is right, of course, but not in a way that helps his argument. He overlooks the fact that law itself is a form of communication within a hierarchical organization. Law has authority because the lawmaker has authority. This is another way of saying that the lawmaker has a right to be obeyed, which is inseparable from the interpreter’s duty to find out what the lawmaker originally meant by the command in question.

Another principled argument for originalism holds that it is part of “our law,” or is simply the American way of constitutional interpretation. Sunstein dismisses this claim, citing numerous Supreme Court precedents from the last several decades that are admittedly not based on an originalist reading of the Constitution. Originalists, of course, know all about these rulings, regard some of them as errors, and contend that the originalist movement seeks to recover the authentic, older tradition of constitutional interpretation from which liberal justices began to depart in the last couple of generations. In response to this potential counter-argument, Sunstein says that while his book “is not the place” to do it, he believes that “we could find countless cases starting in the 1790s that are not originalist, which means that we are dealing with well over two hundred years of practice.” To this the informed originalist will be tempted to reply: “Well, Professor Sunstein, could you cite just a few of these Founding-era non-originalist rulings? Or even just one?” Sunstein makes no effort to back up his remarkable claim. The serious reader will be amazed that the author tried to get away with this evasion, but it is necessary to his bemusing project of trying to give an account of American constitutional interpretation that is based on following John Rawls while ignoring John Marshall.

Sunstein’s pragmatic, consequentialist critique of originalism is no more persuasive. He suggests a variety of frightening, regressive outcomes that originalism might yield in the fields of civil rights and civil liberties. Even if we grant, for the sake of argument, that originalism could not justify the liberal precedents that Sunstein cherishes as “fixed points,” it does not follow that America would today be an illiberal hellscape if originalism had prevailed all along, since in America public policy is not made primarily by the Supreme Court. Is it likely that the nation that enacted the 1964 Civil Rights Act would have persisted in segregating its public schools? Is it likely that the nation that passed the 19th Amendment would have continued to exclude women from the professions? Is it likely that, in a nation that embraced sexual liberation, state governments would have continued to enforce bans on contraception? The answer to these questions is obvious. Like many liberal intellectuals, Sunstein claims to be a proponent of democracy while at the same time seriously doubting the ability of the voters to govern in a sensible and humane manner without close judicial supervision.

In addition, Sunstein’s approach to choosing among the competing theories of interpretation is subject to grave problems. If judges are not bound by the original meaning of the Constitution, if they are free to choose whatever theory of interpretation comports with their own opinion about what would make our system “better,” then why wouldn’t that same freedom exist for other actors in relation to other legal documents? May judges choose a theory of interpretation that they think makes the system “better” when they interpret statutes, or contracts, or wills? May lower-court judges exercise this freedom when they are called upon to interpret the rulings of the Supreme Court? May executive-branch officials pursue this path with, say, court orders, instead of trying to figure out what the court actually meant by them? These questions will occur to any thoughtful reader, and Sunstein makes no serious effort to address them.

Although Sunstein treats originalism with a certain respect, he clearly views its ascendancy today as a threat to his own “fixed points.” Accordingly, he is strenuous in his attempts to rule out its principled claims, boldly asserting more than once that his own pragmatic approach is “the only game in town.” His arguments, however, fall apart on careful examination; and their failure points indirectly but inexorably to the conclusion he wishes to avoid. For those who are interested in fidelity to the Constitution, originalism is “the only game in town.”