Although an inchoate liberty theory of freedom of speech has deep roots in Supreme Court decisions and political history, it has been overshadowed in judicial decisions and scholarly commentary by the marketplace of ideas theory. In this book, Baker critiques the assumptions required by the marketplace of ideas theory and develops the liberty theory, showing its philosophical soundness, persuasiveness, and ability to protect free speech. He argues that First Amendment liberty rights (as well as Fourteenth Amendment equality rights) required by political or moral theory are central to the possibility of progressive change. Problem areas are examined, including the question of whether individual political and civil rights can in principle be distinguished from property rights, freedom of the press, and the use of public spaces for expressive purposes.