American constitutional law is having a “natural law moment,” declared Joel Alicea ’13, a professor at The Catholic University of America Columbus School of Law, during an event at Harvard Law School on April 9. Alicea was delivering the Herbert W. Vaughan Memorial Lecture, a regular series devoted to understanding the founding principles and tenets of American constitutionalism.

According to Alicea, natural law, which is most closely associated with philosophers like Aristotle, Cicero, and Thomas Aquinas, rejects cultural relativism in favor of the idea that there are both objective goods and objective wrongs, which are “understandable in light of human nature,” and can be identified through reason.

The theory is gaining favor among some who study the U.S. Constitution, said Alicea, who is also the co-director of the Project on Constitutional Originalism and the Catholic Intellectual Tradition.

“Something new is happening in American constitutional theory,” he said. “Never before have so many legal scholars sought to ground constitutional theory in the natural law tradition.”

In his talk, Alicea explored how recent efforts to connect constitutional theory to natural law diverge from those of the past, what explains natural law’s ascendancy, and the broader implications of this rise.

Alicea highlighted three main differences between today’s scholarship and previous work that sought to integrate natural law and constitutional theory. First, contemporary scholars are “self-consciously Thomistic” — that is, referencing the theories and work of Thomas Aquinas, an Italian priest and philosopher of the high medieval period — in their approach to natural law. Thomists “expressly adopt Aquinas’s definition of law: ‘an ordinance of reason, for the common good, promulgated by one who had legitimate authority,’” he said.

Today’s scholars “to varying degrees, rely on Thomistic arguments about the nature of political authority, the relationship between reason and emotion in the human person, and the moral obligations of jurists, lawmakers, and citizens in relation to law.”

By contrast, past scholars deployed a more “eclectic” mix of arguments derived from an array of other thinkers, such as Immanuel Kant, John Locke, and even Abraham Lincoln, he said. This “lack of Thomistic grounding,” Alicea added, meant that previous scholars were not “forced to confront whether [their] understanding of the judicial role is compatible with the scope of legitimate judicial authority under the American Constitution.”

Also, modern day scholars “are primarily constitutional theorists, not legal philosophers,” which matters, Alicea said, because the former are “more deeply enmeshed in the specifics of the American constitutional regime” than are legal philosophers. As a result, he continued, contemporary scholars tend to pick a side on the originalism versus non-originalism debate — a fact that underscores another difference: Today’s natural law constitutional theorists “come in originalist and non-originalist varieties.”

Originalism is a method of interpreting the Constitution that prioritizes the original meaning or intent of the nation’s founding document. In contrast to today, earlier natural law constitutional theorists tended to be critics of originalism, said Alicea.

This new link between natural law and originalism also explains why natural law has enjoyed a renaissance in recent decades, in Alicea’s view.

As originalism went from a method of judicial interpretation favored by a minority of the members of the U.S. Supreme Court to the “dominant methodology among federal judges,” including the Court, “the need for worked out, rigorous justifications for originalism are more relevant to legal scholarship than ever before.”

Previous proponents of originalism, such as Antonin Scalia ’60 and Robert Bork, he said, were “wary of making moral truth claims.” But as originalism began to inform majority opinions by the Court, its champions embraced the idea of an objective moral reality, which “opened the door to moral justifications rooted in the natural law tradition.”

But what impact does all of this have on American constitutional theory? Alicea saw three major implications.

“We need to know whether the Constitution furthers the common good, and that requires knowing what the common good is, which requires knowing something about who the human person is, and how we flourish as the distinctive kinds of beings that we are.”

“First, natural law constitutional theories have a smaller gap between their theories of law and their theories of adjudication than other constitutional theories tend to have,” he said.

“In recent years, several scholars, both originalist and non-originalist, have argued that constitutional theorists should focus more on theories of law, rather than on theories of adjudication,” he continued. “They seek to establish a consensus around the law of our Constitution, leaving for another day normative questions like whether we ought to obey the Constitution and how we ought to resolve disputes under the Constitution.”

But the natural law approach rejects this, he said. “If we instead adopt a Thomistic understanding of law, normative evaluation is built into identification of what the law is, since the focal meaning of law requires that law be an ordinance of reason directed toward the common good, and that it be promulgated by a legitimate authority.”

As an example, Alicea said, “if one concludes that the original meaning of the Constitution is the law … it follows that we have a prima facia moral obligation to obey it, since doing so would be good for us both in terms of the law’s content … and in terms of sustaining the authority of its author.”

Second, natural law constitutional theory “widens the scope of inquiry” by involving scholarship from other fields, Alicea said.

While previous scholars like Bork “thought constitutional theory could be largely separated from the domains of philosophy and other disciplines, and confined to more mundane and technical lawyers’ work,” he said, natural law theory is “unavoidably interdisciplinary” because “we cannot adjudicate constitutional disputes without resolving antecedent questions of political morality.”

For instance, Alicea continued, “we need to know whether the Constitution furthers the common good, and that requires knowing what the common good is, which requires knowing something about who the human person is, and how we flourish as the distinctive kinds of beings that we are.”

The final implication of this natural law moment, according to Alicea, is that “natural law constitutional theorists seek to bring the rest of the field into conversation with authors and sources that have too long been neglected in American constitutional theory scholarship.” Those authors include Aristotle and Aquinas, but also other important natural law figures rarely cited by such scholars, including Cicero, Francisco Suárez, and Robert Bellarmine.

All of this, Alicea concluded, makes for an exhilarating time to be a constitutional scholar. “Our natural law moment in constitutional theory holds out the exciting prospect of the discovery — or we might say the rediscovery — of insights and arguments that have lain dormant for all these many years, patiently waiting for us to find them.”

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