This week’s Senate report on the CIA’s use of harsh interrogation methods is neither the first nor the worst time the agency has run afoul of its congressional overseers. Four decades ago, a series of hearings on Capitol Hill helped reveal that the CIA-run Phoenix Program in South Vietnam, working in concert with the U.S. and South Vietnamese militaries, had “neutralized” -- killed, detained or recruited -- as many as 80,000 people suspected of being members of the Communist Vietcong and used gang rape, beatings and electric shock as well as waterboarding to interrogate prisoners. Then in 1975 and 1976, a Senate panel took a broader look into the dark side of the Central Intelligence Agency and found that the nation’s spies seemed to have few limits, with covert activities that included plotting to assassinate foreign leaders, domestic spying and LSD experiments on unwitting subjects.