Pentagon Papers

The Pentagon Papers, officially titled Report of the Office of the Secretary of Defense Vietnam Task Force, is a United States Department of Defense history of the United States' political and military involvement in Vietnam from 1945 to 1967. 
The papers were released by Daniel Ellsberg, who had worked on the study. They were first brought to the attention of the public on the front page of "The New York Times" in 1971. 
A 1996 article in "The New York Times" said that the "Pentagon Papers" had showed, among other things, that the Johnson Administration "systematically lied, not only to the public but also to Congress."