Eugene Wambaugh (February 29, 1856 – August 6, 1940) was an American legal scholar.
From 1906 to 1913, he was a member of the American Political Science Review, and from 1908 to 1912 served as special attorney of the United States Bureau of Corporations.
His publications include: Wambaugh was an adviser to the State Department on war problems in 1914 and was discharged honorably from the U.S. Army in 1919 with the rank of colonel.
Wambaugh devised the eponymous Wambaugh's Inversion Test, which provides that to determine whether a judicial statement in a common law case is ratio or obiter, you should invert the argument, that is to say, ask whether the decision would have been different, had the statement been omitted.
Their children were Sarah, an international authority on plebiscites, and Miles, a Boston attorney.