The journalistic professionalism and integrity of I. F. Stone derived from his intellectual willingness to scour and devour public documents, to bury himself in "The Congressional Record", to study the transcripts of obscure congressional committee hearings, debates and reports. He prospected for news nuggets — published as boxed paragraphs in his weekly newsletter — such as contradictions in the line of official policy, examples of bureaucratic mendacity and political obscurantism. Stone especially sought evidence of the U.S. government's legalistic incursions against the civil liberties and the civil and political rights of American citizens.