The facts that are relevant to this appeal are as follows. On July 4, 1977, appellant Douglass crossed a fence of the base and entered that portion of the base situated therein to participate along with others in a “picnic” intended as a form of civil disobedience. To accomplish the warning required by
18 U.S.C. s 1382, the Commanding Officer at Bangor, on July 5, 1977 issued, and appellant received, a “bar letter” ordering him not to reenter, “or to be found within the limits of” the base. (R.T. 34). On July 20, following the arrest of three individuals, appellant again entered military property to inquire about their status. He was warned at that time that he had been barred and would be arrested if he should reenter. The next day appellant and others were seen near the old Main Gate of the base. A number of protesters entered the property to leaflet workers. Appellant remained an onlooker apart from the others. Upon seeing their arrest, however, appellant entered military property, headed for a phone booth used by the public for the purpose of calling attorneys and reporters about the incident, and was arrested upon entering the booth. The booth was located behind a clearly marked white boundary line, but was outside the fence of the base and on the street side of the guard house. At his trial before a magistrate, appellant testified that he was aware that he was entering government property. He was found guilty and sentenced to five days imprisonment.