Free speech is first examined as a political principle, with emphasis on the justifications commonly advanced for freedom of speech and the kinds of communications to which the principle of free speech applies. The analysis then focuses on communications for which criminal liability is fixed including threats and solicitations to crime. The discussion also considers the types of activities that should be considered to be "speech" within the meaning of the first amendment and what tests the courts should use in deciding whether particular criminal statutes should be held constitutional. Chapter reference notes and index