The Alien Tort Statute and Federal Common Law: A New Approach

International human rights cases brought under the Alien Tort Statute (ATS) (1) raise a host of issues: whether the alleged conduct violates well-established international law, (2) the applicability and scope of various forms of secondary liability, (3) the contours of state action, (4) the extension of liability to private individuals and corporations, (5) the possible award of punitive damages, (6) application of alter ego and veil piercing doctrines, (7) whether plaintiffs must exhaust their remedies, (8) and so on. After Sosa v. Alvarez-Machain, (9) courts and commentators have generally understood some of these issues as governed by federal common law (10) and others by international law; the choice between these two sources of law is often presented as binary. (11) Some forms of this approach can be analogized to Bivens (12) actions, with federal common law providing the cause of action and remedy, while international law supplies the conduct-regulating rules of decision. (13) It may be fair to say that the binary approach has become the prevailing narrative of ATS litigation. There is, however, another way to understand the relationship between federal common law (14) and international law in ATS cases. Federal common law might be understood as applying to all of these aspects of ATS litigation, including the substantive standard for liability, although some aspects of that federal common law (including the substantive standard of liability) are closely linked to international law. Thus, the relationship between federal common law and international law is not binary but instead is best understood on a continuum, with certain aspects of ATS litigation governed by federal common law that is tightly linked to international law, other aspects governed by federal common law that is not derived from international norms, and still others that fall somewhere in between. The extent to which federal common law is tied to international law in ATS cases is determined then by the inferred intentions of Congress and separation of powers because these are the bases upon which the development of federal common law in ATS cases is authorized after Sosa. (15) Congressional authorization and separation-of-powers considerations are linked, however, to the content of international law. Finally, according to this approach, the federal common law applied in ATS cases is best understood as sui generis--it is its own enclave of federal common law that is not necessarily binding or preemptive outside the context of ATS litigation. (16) These distinctions would not make a difference in the outcome of Sosa, of course. Whether we call it customary international law, or "international law cure common law," (17) Alvarez-Machain's ATS claim based on short-term unlawful detention did not meet the high bar imposed by the Sosa Court. (18) Nevertheless, applying international law as part of a federal common law that governs all aspects of ATS may change the outcome of cases that turn on issues like secondary and corporate liability. Moreover, it is preferable on descriptive, doctrinal, and normative grounds, as Part I below explains. Part I begins by describing the prevailing views on federal common law and the rule of decision in ATS cases. It then explains that applying federal common law to all substantive issues in ATS cases is preferable. In short, no issues in ATS cases are actually resolved through application of "pure" international law--instead, the law applied is filtered through the particular history and origins of the ATS itself, along with other factors unique to the United States. Descriptively, the federal common law approach is more accurate. Doctrinally, courts and litigants have wasted much time and energy choosing between "international" and "domestic" law, neither of which alone provides a satisfactory resolution of most contested issues. Normatively, federal courts may avoid (in whole or in part) the charge that they misunderstand customary international law, and they may be in a position to develop some norms of customary international law that are not yet fully developed, depending in part on the intentions of Congress and the executive branch. …