The Supreme Court’s recent decision regarding corporate spending on political advocacy—Citizens United v. Federal Election Commission—provoked the widespread renewal of a longstanding liberal complaint: namely, that the conservative critique of judicial activism is mere hypocrisy. In this case, it was suggested, conservative justices, applauded by conservative commentators, struck down a democratically enacted law and overturned long established judicial precedents. Surely, the argument runs, this is judicial activism, and surely it reveals the critique of judicial activism as just a convenient tool by which conservatives decry decisions to which they object for political reasons, cloaking their real concerns in feigned constitutional principles.

Though common, this charge of hypocrisy sheds little real light on the questions in relation to which it is invoked, for several reasons. First, it does nothing to help us determine the relative merits of the liberal and conservative positions with regard to the proper exercise of the judicial power. After all, the charge clearly cuts both ways. In regard to Citizens United, liberals have complained not only about conservative inconsistency on the matter of judicial activism, but also about the supposed activism of the decision itself. Thus conservatives might well ask these liberal critics: where was your hot indignation about judicial activism when the Court, as recently as nineteen months ago, issued its ruling in Boumediene v. Bush? In that case, the Court, to widespread liberal acclaim, reinterpreted key precedents and struck down Congressional enactments on the basis of a hitherto unknown right of alien enemy combatants to habeas corpus review. Liberals no less than conservatives, it seems, can be charged with a selective opposition to judicial activism.

Second, charges of inconsistency regarding judicial activism are often unhelpful because they routinely use the term too loosely—that is, without reference to the merits of the specific constitutional arguments in question. When the Court strikes down a law or overturns precedent, those who disagree with the ruling will generally complain of judicial activism. Yet it is agreed on all sides in American politics that it is sometimes perfectly appropriate for the Court to strike down laws or overturn precedents. After all, from the beginning of the American republic it has been understood that the exercise of judicial review is an inescapable part of the Court’s function, and judicial review is inseparable from the possibility of declaring unconstitutional laws void and erroneous precedents inoperative. If judicial activism is to have any useful meaning, then, it will have to be understood as the exercise of judicial review in a way that is not warranted by the Constitution. The purpose of judicial review, however, is to safeguard and enforce the law of the Constitution. Judicial activism, therefore, is best understood not as the striking down of laws or reversing of precedents—both of which may be required by the Court’s duty in a particular case—but as the substitution of the Court’s political, policy, or moral judgments for the requirements of the law and the Constitution. On this understanding, it is worth observing, the Court could engage in judicial activism even when upholding a law or precedent, if it does so contrary to the clear meaning of the Constitution.

This brings us, in the third place, to a deeper problem: loosely framed charges of judicial activism, flung selectively by both conservatives and liberals, tend to obscure the disturbing extent to which much of the modern Supreme Court’s jurisprudence is itself a product of and a continuing invitation to a problematic judicial activism in the precise sense noted above. That is, the intellectual framework that all the justices, left and right, have inherited, and within which they think they must work, arose from and invites the substitution of their moral and political convictions for the law of the Constitution.

This problem is evident in the Court’s opinion in the Citizens United case, whether or not one agrees with its ruling. In deciding the question before them, the majority had recourse not only to the Constitution, but also to a Court-created judicial doctrine known as “strict scrutiny.” Strict scrutiny is ordinarily applied to laws that (among other things) impose on what the Court regards as “fundamental rights”—such as, in Citizens United, the freedom of speech. The test reverses the usual presumption of constitutionality. That is, when strict scrutiny is invoked, the burden of proof is not on the litigant challenging the law to demonstrate its unconstitutionality, but on the government to justify its constitutional legitimacy. Despite weighting the scales against such laws, strict scrutiny further stipulates that they can be upheld if they serve a “compelling governmental interest” by the “least restrictive means.” In other words, a law may constitutionally intrude on a fundamental right, if it is necessary to serve some important objective and there is no other way to do so that is less of an intrusion.

Strict scrutiny, however, is itself a product of judicial activism understood as the substitution of the opinions of judges for the requirements of the Constitution. As Justice Felix Frankfurter—one of the Supreme Court’s great defenders of judicial restraint—pointed out when the elements of the strict scrutiny test first began to emerge in the mid-twentieth century, there is nothing in the Constitution on the basis of which an impartial reader could conclude that some kinds of laws are entitled to a presumption of constitutionality while others are not. There is, in fact, nothing in the Constitution to suggest that some governmental objectives are more “compelling” than others, or that some rights are more “fundamental” than others. Such categories were utterly unheard of in American constitutional jurisprudence during the nation’s first century and a half. They were unknown to Chief Justice Marshall, and even to zealous judicial defenders of rights in the early decades following the ratification of the Fourteenth Amendment. These concepts are not requirements of the Constitution but the inventions of judges seeking to guide the Court to outcomes they approved on non-constitutional grounds—namely, their own assessment of what would be good and just.

A product of judicial activism, strict scrutiny is also an invitation to ongoing judicial activism. Most obviously, its abandonment of the traditional presumption of constitutionality gives the Court much greater freedom to strike down laws that have been approved by majorities of the people’s representatives. Perhaps more important, by requiring the Court to ask questions to which the Constitution provides no answers, strict scrutiny calls judges to substitute their own convictions for those of legislators. What counts as a compelling governmental interest? The Constitution, again, is silent on this question. The answer is not a matter of constitutional law but of political philosophy. Some people think that the promotion of greater economic equality is a compelling governmental interest, while others do not. Some people think that the fostering of traditional sexual morality is a compelling governmental interest, which others would deny. Such disputes are subject to more or less plausible philosophic reasoning, but not to constitutionally conclusive reasoning. When a Court overturns a law based on arguments that are not constitutionally compelling, however, it has not vindicated the Constitution but simply decided to prefer what seems reasonable to it over what seemed reasonable to legislators. It has, in other words, engaged in judicial activism.

Nor is it the case, as some might contend, that the Court could find clear guidance on what constitutes a compelling governmental interest by looking not to its members’ convictions but to the dominant practices and values of contemporary society. The very fact that cases arise in which the parties contend over what is a compelling governmental interest shows that society is characterized as much by division as by agreement on such questions. And when the Court decides to side with one understanding over another without a constitutional reason to do so, it has again engaged in what can plausibly be called judicial activism.

None of this is necessarily to say that the Supreme Court erred in its decision in Citizens United. The case involved a law that regulated political speech. Accordingly, even dispensing with strict scrutiny, a Court could reasonably conclude that while such a law is entitled, like any other, to a presumption of constitutionality, that presumption is here overcome by the law’s infringement on a freedom expressly enshrined in the text of the Constitution. My point is that, even if Citizens United was correctly decided, the use of tests like strict scrutiny, now deeply entrenched in the Court’s jurisprudence, drive the Court into kinds of inquiries that almost inevitably make even the most sincere critics of judicial activism engage in it themselves.

Judicial activism is a problem of profound significance for the American republic. By relying on the opinions of judges instead of principles grounded in the constitution, it represents a denial of the rule of law that was the very purpose of the Constitution. More than that, because the concepts essential to modern judicial activism are so pliable, and because the composition of the Court changes so regularly, judicial activism turns out to be incompatible with the rule of law in any sense. The Court’s jurisprudence becomes instead a record of ad hoc approvals and disapprovals on the basis of which no clear predictions of future rulings is possible, a set of arbitrary judgments that is the opposite of the rule of law. If this very real and serious problem is to be addressed, our concerns about judicial activism will have to become more than just rhetorical weapons wielded when politically convenient. We will instead have to reconsider the role the Court has assumed for itself over the last half century or more.