War Powers Litigation Initiated by Members of Congress Since the Enactment of the War Powers Resolution [June 22, 2011] [open pdf - 229KB]
"Article I, Section 8, of the Constitution confers on Congress the power to 'declare War.' Modern Presidents, however, have contended that, notwithstanding this clause, they do not need congressional authorization to use force. Partly in response to that contention, and because of widespread concern that Congress had allowed its war power to atrophy in the Korean and Vietnam conflicts, Congress in 1973 enacted the War Powers Resolution (WPR, P.L. 93-148). Among other things, the WPR generally requires the President to report to Congress within 48 hours when, absent a declaration of war, U.S. Armed Forces are introduced into 'hostilities or ... situations where imminent involvement in hostilities is clearly indicated by the circumstances.' After a report is submitted or required to be submitted, the WPR requires that the forces be withdrawn within 60 days (90 days in specified circumstances) unless Congress declares war or otherwise authorizes their continued involvement. […] This report summarizes the seven cases initiated by Members of Congress in which final rulings were reached, which concerned U.S. military activities in El Salvador, Nicaragua, and Grenada; military action taken during the Persian Gulf conflict between Iraq and Iran; U.S. activities in response to Iraq's invasion of Kuwait (prior to the congressional authorization); and U.S. participation in NATO's action in Kosovo and Yugoslavia. This report also briefly discusses the current legal challenge to enjoin further military action against Libya, and discusses more generally the debate surrounding the WPR's application to these military operations. This report will be updated as circumstances warrant."
CRS Report for Congress, RL30352