In what played out to be the most dramatic exchange of the hearings, McCarthy responded to aggressive questioning from Army counsel Joseph Welch.
On June 9, 1954, day 30 of the hearings, Welch challenged Cohn to give McCarthy's list of 130 subversives in defense plants to the office of the FBI and the Department of Defense "before the sun goes down".
In response to Welch's challenge, McCarthy suggested that Welch should check on Fred Fisher, a young lawyer in Welch's own Boston law firm whom Welch had planned to have on his staff for the hearings.
McCarthy then mentioned that Fisher had once belonged to the National Lawyers Guild (NLG), a group which Attorney General Brownell had called "the legal bulwark of the Communist Party".

Welch revealed he had confirmed Fisher's former membership in the National Lawyers Guild approximately six weeks before the hearings started.
After Fisher admitted his membership in the National Lawyers Guild,  Welch decided to send Fisher back to Boston.
His replacement by another colleague on Welch's staff was also covered by The New York Times.
Welch then reprimanded McCarthy for his needless attack on Fisher, saying "Until this moment, Senator, I think I never really gauged your cruelty or your recklessness."
McCarthy, accusing Welch of filibustering the hearing and baiting Cohn, dismissed Welch's dissertation and casually resumed his attack on Fisher, at which point Welch angrily cut him short:
Senator, may we not drop this?
We know he belonged to the Lawyers Guild ... Let us not assassinate this lad further, Senator; you've done enough.
Have you no sense of decency, sir?
At long last, have you left no sense of decency?

Welch excluded himself from the remainder of the hearings with a parting shot to McCarthy: "Mr. McCarthy, I will not discuss this further with you... You have seen fit to bring [the Fisher/NLG affair] out, and if there is a God in heaven, it will do neither you nor your cause any good!
I will not discuss it further... You, Mr. Chairman, may as you will, call the next witness!"
After Welch deferred to Chairman Mundt to call the next witness, the gallery burst into applause.
In what played out to be the most dramatic exchange of the hearings, McCarthy responded to aggressive questioning from Army counsel Joseph Welch. On June 9, 1954, day 30 of the hearings, Welch challenged Cohn to give McCarthy's list of 130 subversives in defense plants to the office of the FBI and the Department of Defense "before the sun goes down". In response to Welch's challenge, McCarthy suggested that Welch should check on Fred Fisher, a young lawyer in Welch's own Boston law firm whom Welch had planned to have on his staff for the hearings. McCarthy then mentioned that Fisher had once belonged to the National Lawyers Guild (NLG), a group which Attorney General Brownell had called "the legal bulwark of the Communist Party".
Welch revealed he had confirmed Fisher's former membership in the National Lawyers Guild approximately six weeks before the hearings started. After Fisher admitted his membership in the National Lawyers Guild,  Welch decided to send Fisher back to Boston. His replacement by another colleague on Welch's staff was also covered by The New York Times. Welch then reprimanded McCarthy for his needless attack on Fisher, saying "Until this moment, Senator, I think I never really gauged your cruelty or your recklessness." McCarthy, accusing Welch of filibustering the hearing and baiting Cohn, dismissed Welch's dissertation and casually resumed his attack on Fisher, at which point Welch angrily cut him short:
Senator, may we not drop this? We know he belonged to the Lawyers Guild ... Let us not assassinate this lad further, Senator; you've done enough. Have you no sense of decency, sir? At long last, have you left no sense of decency?
Welch excluded himself from the remainder of the hearings with a parting shot to McCarthy: "Mr. McCarthy, I will not discuss this further with you... You have seen fit to bring [the Fisher/NLG affair] out, and if there is a God in heaven, it will do neither you nor your cause any good! I will not discuss it further... You, Mr. Chairman, may as you will, call the next witness!" After Welch deferred to Chairman Mundt to call the next witness, the gallery burst into applause.
Army–McCarthy hearings