 Proposed legislation (bills) that is passed by both houses of Congress is presented to the President, in their capacity as head of the Executive Branch of the U.S. federal government.If the President approves of the bill, they sign it into law.According to of the Constitution, if the President does not approve of the bill and chooses not to sign, they may return it unsigned, within ten days, excluding Sundays, to the house of the United States Congress in which it originated, while the Congress is in session.