Reviewed by: Justice in Blue and Gray: A Legal History of the Civil War Mark Tushnet (bio) Justice in Blue and Gray: A Legal History of the Civil War. By Stephen C. Neff. (Cambridge, Mass.: Harvard University Press, 2010. Pp. 350. Cloth, $45.00.) Stephen Neff teaches international law, and that shows from the first page of Justice in Blue and Gray, where it is already clear that international law is the book's focus. This focus can most obviously be contrasted with that of the most distinguished predecessor to Neff's work, James G. Randall's Constitutional Problems under Lincoln, originally published in 1926 and then revised in 1951. Randall does not ignore international law—he could not without distorting his legal analysis—but it is secondary to [End Page 279] Randall, domestic constitutional law primary. Neff's reversal of priorities is signaled by the fact that whereas Randall cites founders of public international law Emmerich de Vattel three times and Francis Lieber not at all, Neffcites Vattel on eight pages and throughout his book cites Lieber and the Lieber Code, a "legal masterpiece" which codified the laws of war in early 1861 (57). Legal issues associated with the Civil War have received attention more recently in Daniel Farber's Lincoln's Constitution (2003) and Mark Neely's The Fate of Liberty: Abraham Lincoln and Civil Liberties (1991), both fine books that are narrower in scope than Neff's. As Neff and Farber make clear, these issues receive attention today in part because they remind us of issues raised by the conduct of U.S. military operations in ongoing traditional wars in Iraq and Afghanistan and in the apparently novel—but perhaps not so special legally—operations against terrorists on U.S. soil and elsewhere. Yet, while recurrently mentioning the laws of war today, Neff is far less present-minded than Farber. Neff addresses the early 1860s, expanding the view to a short period after 1865 because the international law of war was mostly customary international law, not treaty-based. Customary international law rests in large part on state practice and can be changed by new state practice that departs from—and might be thought inconsistent with—widespread practices by other states at the same time. One cannot know immediately whether an apparent departure from general state practice is a violation of customary international law or an indication of a nascent change in that law until the international legal system reacts to it. Neff begins appropriately by distinguishing between a nation's sovereign powers, regulated by its domestic constitution, and its powers under international law as a belligerent, regulated by the international law of war, conventionally divided into jus ad bellum (the law dealing with the initiation of hostilities) and jus in bello (the law dealing with actions such as blockades and the treatment of enemy soldiers and civilians seized during military action). Jus ad bellum plays a relatively minor part in Neff's account, primarily through that doctrine's recognition that defiance of domestic law within a nation's borders can become so widespread and organized as to amount to a civil war, thereby authorizing a nation to take actions consistent with the international law of war on its own territory. Neff shows that the principle that sovereign nations could act as belligerent powers within their own borders was embedded in the international law of war in 1861. [End Page 280] The primary questions raised by the distinction between the powers of a sovereign and a belligerent are whether, how, and to what extent the U.S. Constitution regulates actions that are consistent with international law, that is, actions taken in a belligerent rather than a sovereign capacity. Some answers are reasonably clear. The "commander in chief" clause, for example, probably resolves most questions of separation of powers once hostilities have commenced by conferring on the president the power to take belligerent acts in the absence of express congressional prohibition. More troublesome than the allocation of powers within the national government are substantive limitations on government powers. Here are many distinctions to be drawn: between actions taken on U.S. soil and those taken outside the United States...