"We have examined three types of 'intelligence' activities affecting the rights of American citizens. The first is intelligence collection -- such as infiltrating groups with informants, wiretapping, or opening letters. The second is dissemination of material which has been collected. The third is covert action designed to disrupt and discredit the activities of groups and individuals deemed a threat to the social order. These three types of 'intelligence' activity are closely related in the practical world. Information which is disseminated by the intelligence community or used in disruptive programs has usually been obtained through surveillance. Nevertheless, a division between collection, dissemination and covert action is analytically useful both in understanding why excesses have occurred in the past and in devising remedies to prevent those excesses from recurring."
Intelligence Activities and the Rights of Americans - Book II (1976)