The Senate passed the amendment for the first time on 14 June. While awaiting action in the House of Representatives, Nixon vetoed separate legislation that would have ended the bombing in Cambodia. Finally, a modified Case‐Church amendment was passed by the Senate on 29 June by a 63–26 vote. It allowed the bombing in Cambodia to continue until 15 August. After that date, all use of the American military was prohibited in Southeast Asia unless the president secured Congressional approval in advance. The proponents of the ban did not know that Nixon had, in fact, secretly promised South Vietnam's president Nguyen Van Thieu that the United States would resume bombing in North and South Vietnam if he determined it necessary to enforce the peace settlement. The Case‐Church amendment, therefore, marked the final end to direct American military involvement in Southeast Asia.
LeRoy Ashby and and Rod Gramer , Fighting the Odds: The Life of Senator Frank Church, 1994.
David F. Schmitz
"Case‐Church Amendment." The Oxford Companion to American Military History. . Encyclopedia.com. (July 18, 2018). http://www.encyclopedia.com/history/encyclopedias-almanacs-transcripts-and-maps/case-church-amendment
"Case‐Church Amendment." The Oxford Companion to American Military History. . Retrieved July 18, 2018 from Encyclopedia.com: http://www.encyclopedia.com/history/encyclopedias-almanacs-transcripts-and-maps/case-church-amendment