The House of Representatives on Thursday approved the Iran War Powers resolution – an effort to restrain President Donald Trump’s ability to use military action against Iran without congressional approval – with the support of three Republicans. Republicans Reps. Matt Gaetz and Francis Rooney of Florida as well as Rep. Thomas Massie of Kentucky all crossed party lines to vote in favor of the resolution. On the Democratic side, Reps. Ben McAdams of Utah, Joe Cunningham of South Carolina, Elaine Luria of Virginia, Kendra Horn of Oklahoma, Stephanie Murphy of Florida, Josh Gottheimer of New Jersey, and Max Rose and Anthony Brindisi of New York all opposed it. The measure, which passed by a nearly party line vote of 224-194 on Thursday evening, will next go to the Senate. The structure of the House resolution is unique, however, calling into question whether it is actually legally binding. It was introduced as a concurrent resolution, a type of resolution often used for “sense of Congress” bills. They don’t go to the President for a signature, and they aren’t legally binding. But House Democrats are arguing that concurrent resolutions under the War Powers Act are a special case, and they are legally binding. Republicans, however, say the resolution is not binding. Rep. Elissa Slotkin of Michigan, a former CIA analyst and freshman Democrat, is the sponsor of the resolution, which calls on the President “to terminate the use of United States Armed Forces to engage in hostilities in or against Iran” unless Congress declares war or enacts “specific statutory authorization” for the use of armed forces.