Policy Innovations Digital Magazine (2006-2016): Innovations: Good Ideas Are From Anywhere

The recent confirmation hearings of Supreme Court nominee Sonia Sotomayor covered everything from her opinions on contested cases to her wider judicial philosophy. While the process focused on American constitutional law, it also touched upon a central issue of the international legal and moral order.

In April 2009, Judge Sotomayor spoke before the American Civil Liberties Union of Puerto Rico. In her presentation she addressed the role of international law in American judicial decision making, arguing that international law provides a source of ideas for understanding not only cases dealing with international affairs but American law as well.

During her hearing before the U.S. Senate Judiciary Committee, Sotomayor faced questions concerning her stance on the role of international law. Committee member John Cornyn (R-Texas) telegraphed his concerns on this issue in a post on his website prior to the hearings: In my view, the Constitution does not give federal judges the "freedom of ideas" to devise new ways to limit the democratic process. Judges must follow the law and the Constitution. They are not "free" to enact "good ideas" into law when their "creative juices" flow. That is a job for the people acting through their elected branches, not a job for judges tasked with following the law. In light of Judge Sotomayor's address at the ACLU of Puerto Rico, I hope Judge Sotomayor can explain how she reconciles her views of foreign and international law with the properly limited role of the judiciary in a democratic society. Sotomayor responded that she found foreign law useful as a point of "comparison" with American law, a comparison that can help in decision making.

Sotomayor is not the first American judge to view international law in this manner, nor is she the first to find her ideas the subject of political debate. In a conversation between Justices Steven Breyer and Antonin Scalia at the American University School of Law, Breyer argued along lines similar to Sotomayor. Even more controversially, Justice Breyer has cited foreign law in opinions before the Supreme Court, a strategy that contradicts Justice Scalia's "originalist" interpretation of the Constitution. Justice Ruth Bader Ginsberg has also highlighted the relevance of international and foreign law for understanding cases before the bench, while Chief Justice John Roberts and Justice Samuel Alito have argued that foreign law should be kept separate from arguments and opinions in U.S. law.

What are we to make of this view that international law provides good ideas or useful comparisons for interpretations of American law? To consider international law as a set of ideas rather than a set of binding injunctions that all nations are obligated to follow stands in contradiction to the standard view of international law. The idea that international law is merely a "set of ideas" would undoubtedly be anathema to members of the American International Law Association.

But it is important to clarify what the debate is really about. Judge Sotomayor and Justice Breyer both fully appreciate the binding nature of international law, but only when it has been turned into U.S. domestic law through an act of the U.S. Congress. This means that neither rejects the importance of international law, a fact that any U.S. Senator who understands the role of treaties would also understand.

What Senator Cornyn is actually objecting to is the use of "foreign opinion" or, more accurately, foreign constitutional law in aiding U.S. judicial decision making. For Sotomayor and Breyer, the ideas to which they are referring are usually foreign constitutional norms, that is, laws and ideas drawn from different national contexts. For example, Justice Breyer has drawn upon the opinion of other national contexts to support his views on the death penalty.

This strategy of judicial reasoning opens up a larger question that should be of interest to those who think about ethics and international affairs. To assume that there are ideas floating about in the global ether that any judge could pull out and use in making decisions about American cases is parallel with the idea that there is a set of shared ethical norms that shape not only domestic law but also international law and international affairs more broadly. Indeed, the foundation of the Carnegie Council for Ethics in International Affairs is premised upon there being such ideas, norms, rules and, yes, even laws.

How should we understand such ideas? Are they binding? What is the foundation of such ideas when they become laws? One way to understand them is through the lens of natural law. This concept, not much in favor within American jurisprudence beyond some conservative or Roman Catholic thinkers, arises from the medieval scholastic notion that because there is a shared human nature, the ethical and legal precepts that govern human communities everywhere have strong similarities. Because natural law is drawn essentially from Christian philosophy, particularly St. Thomas Aquinas, it is unlikely that Sotomayor or Breyer or even Justice Scalia would point directly to it as influential in their decision making.

But natural law has not remained purely within the province of Christianity, as evidenced by the way in which the just war tradition draws upon it. In the 17th century, figures such as Hugo Grotius and Samuel Pufendorf secularized natural law by moving it away from its reliance on the Scholastics and Christian scriptures. As James Turner Johnson has so ably demonstrated, this move within natural law theory allowed the just war tradition to become a non-Christian idea that eventually informed the construction of international law. Larry May's work on the just war tradition also draws on this more secular understanding of natural law, particularly Grotius, in developing his understanding of just war.

In the American judicial context, there seems to be a vague correspondence between natural law, particularly its secular variant, and the idea that judges can look to non-American contexts in their constitutional interpretation. Perhaps there are constitutional norms in the international system that can be employed by judges in different national contexts and even by the international judiciary. The influence of American political thought on the formation of the United Nations suggests that the influence of the global constitutional context on the United States would be more like a boomerang effect than an imposition of something radically new.

If this were the case, perhaps international legal and ethical theorists would be wise to return to debates about natural law and how such general moral norms can play a role in both national and international judicial contexts. One need not necessarily adopt the Christian background of natural law (although one should understand it) in order to think through its implications for international affairs. Indeed, the fact that the just war tradition has its origins in Christian thought does not render it impractical for making judgments about war and peace today.

In pushing forward natural law debates, one could start thinking through whether or not the existence of shared ideas is evidence of a global constitutional order, one that includes both shared values and institutional structures that mirror the checks and balances of the American system. This is not to say that a global constitutional order would mimic the American one, but it should be of some comfort to American conservatives that ideas from the Federalist Papers and early American legal theorists such as James Wilson found favor in the creation of the European Union and the United Nations.

The point here is not to suggest that Judge Sotomayor would bring a natural law or global constitutional approach to her decision making on the U.S. Supreme Court. Rather, those concerned with constitutions, national and international, could do well to draw upon the rich tradition of natural law when assessing whether "good ideas" can be drawn from a wide range of national contexts to shape interpretations of the U.S. Constitution. If there is a shared human nature, then ideas from around the world indeed participate in a natural law, one that may well bring us closer to a global constitutional order founded on justice, peace, and human rights.