Michael W. Lewis

Interpretations of IHL in Tribunals of the United States

Tribunals of the United States have been interpreting IHL ever since the nation was founded. Even before the enactment of the US Constitution, several Founding Fathers believed that membership in the community of nations should be a fundamental aim of the new republic. In the more than two centuries since the Constitution’s enactment, US policy and practice have typically remained within the membership conception. This chapter has describes both how the membership conception has influenced US judicial interpretations of IHL and how these interpretations have in turn influenced the international conception of that body of law. US departures from the membership conception of IHL have usually involved measures taken by the executive branch. US tribunals have responded to these departures in a variety of ways. Sometimes they have accepted these initiatives, but often they have rejected them or tailored the measures to IHL principles. This pattern emerged after the Civil War, when the US Supreme Court held in Ex parte Milligan that a military commission could not try a non-belligerent for acts committed outside the theater of war. In In re Yamashita, the Supreme Court upheld a military commission conviction based on a then-novel theory of command responsibility. That doctrine went on to become a key building block for international tribunals.The September 11 attacks provide the latest illustration of the membership argument. After the executive branch responded to the attacks with efforts to change IHL rules on interrogation, detention, and the jurisdiction of military commissions courts pushed back. These responses were often effective, although the Supreme Court’s decision in Hamdan v. Rumsfeld classifying the struggle with al Qaeda as a NIAC may have raised more questions than it answered. With regard to detention courts have applied IHL principles to determine membership in armed groups and the US has begun to implement administrative reviews based on the Fourth Geneva Convention. As of the writing of this chapter, issues regarding military commission jurisdiction are still working their way through US courts. However, the D.C. Circuit’s decision in Hamdan v. United States vacating a conviction for material support of terrorism in the absence of evidence that the defendant had committed an established war crime reaffirmed the US Constitution’s commitment to international law.