Lewis is Professor of Political Science at Tulane University.
Among his publications are: Paraguay under Stroessner (1980); Socialism, Liberalism, and Dictatorship in Paraguay (1982); The Crisis of Argentine Capitalism (1990); Latin Fascist Elites.
The Mussolini, Franco and Salazar Regimes (2003); Guerrillas and Generals, The Agony of Argentine Capitalism: From Menem to the Kirchners and Authoritarian Regimes in Latin America: Dictators, Despots, and Tyrants.