Public Law 503, enacted by the Congress in March 1942, implemented Executive Order 9066.
Seventy-seventh Congress of the United States of America; At the Second Session
Begun and held at the City of Washington on Monday, the fifth day of January, one thousand nine hundred and forty-two
To provide a penalty for violation of restrictions or orders with respect to persons entering, remaining in, leaving, or committing any act in military areas or zones.
Be it enacted by the Senate and House of Representatives of the United States of America assembled, That whoever shall enter, remain in, leave, or commit any act in any military area or military zone prescribed, under the authority of an Executive order of the President, by the Secretary of War, or by any military commander designated by the Secretary of War, contrary to the restrictions applicable to any such area or zone or contrary to the order of the Secretary of War or such military commander, shall, if it appears that he knew or should have known of the existence and the extent of the restrictions or order and that his act was in violation
thereof, be guilty of a misdemeanor and upon conviction shall be liable to a fine not to exceed $5,000 or to imprisonment for not more than one year, or both, for each offense.
Speaker of the House of Representatives
President of the Senate pro tempore
Approved, March 21, 1942
Source: Public Law 503, March 21, 1942. National Archives