Apolice officer spent several hours using binoculars to observe an older man loitering on a college campus. the man, who was shabbily dressed and carrying a backpack, would approach certain students as they walked by him, and after a brief conversation with them, discreetly pass the students a small envelope in exchange for cash. the officer stopped the man under suspicion that he was dealing drugs. the man was not dealing drugs, but instead had been soliciting donations for a radical political group. the man grew irate when the officer opened one of the envelopes in question and discovered that they only contained literature about the group. the officer then frisked the man and discovered an illegal weapon taped to his leg. the officer immediately arrested the man.