Question: What U.S. Senator from the state of Wisconsin was the play The Investigator based on?

full_context: Document 1: Card-carrying Communist: "Card-carrying communist" is a term popularised during the Second Red Scare as a label for members of communist and far-left organisations, especially the US Communist Party. The term is still considered derogatory when used in its Cold War context.
Document 2: Everett Dirksen: Everett McKinley Dirksen (January 4, 1896 – September 7, 1969) was an American politician of the Republican Party. He represented Illinois in the United States House of Representatives and the United States Senate. As Senate Minority Leader from 1959 to 1969, he played a highly visible and key role in the politics of the 1960s. He helped write and pass the Civil Rights Act of 1964 and the Civil Rights Act of 1968, both landmark pieces of legislation during the Civil Rights Movement. He was also one of the Senate's strongest supporters of the Vietnam War and was known as "The Wizard of Ooze" because of his flamboyant oratorical style.
Document 3: Esther Brunauer: Esther Caukin Brunauer (July 7, 1901 – June 26, 1959) was a longtime employee of the American Association of University Women (AAUW) and then a U.S. government civil servant, who with her husband was targeted by Senator Joseph McCarthy's campaign against U.S. State Department officials whose loyalty to the U.S. he questioned.
Document 4: House Un-American Activities Committee: The House Un-American Activities Committee (HUAC; a.k.a., House Committee on Un-American Activities, HUAC or HCUA) was an investigative committee of the United States House of Representatives. The HUAC was created in 1938 to investigate alleged disloyalty and subversive activities on the part of private citizens, public employees, and those organizations suspected of having communist ties. In 1969, the House changed the committee's name to "House Committee on Internal Security". When the House abolished the committee in 1975, its functions were transferred to the House Judiciary Committee.
Document 5: Eugene McCarthy: Eugene Joseph McCarthy (March 29, 1916December 10, 2005) was an American politician, poet, and a long-time Congressman from Minnesota. He served in the United States House of Representatives from 1949 to 1959 and the United States Senate from 1959 to 1971. McCarthy sought the Democratic nomination in the 1968 presidential election, challenging incumbent Lyndon B. Johnson on an anti-Vietnam War platform. McCarthy would unsuccessfully seek the presidency five times altogether.
Document 6: Roy Cohn: Roy Marcus Cohn ( ; February 20, 1927 – August 2, 1986) was an American attorney. During Senator Joseph McCarthy's investigations into Communist activity in the United States during the Second Red Scare, Cohn served as McCarthy's chief counsel and gained special prominence during the Army–McCarthy hearings.
Document 7: Revolt of the Beavers: Revolt of the Beavers was a children's play put on by the Federal Theater Project by Oscar Saul and Louis Lantz. One critic described the play as "Marxism a la Mother Goose". The show ran at the Adelphi Theatre in New York City from May 20, 1937, to June 19 of that year. Jules Dassin and John Randolph were among the play's cast.
Document 8: United States House Select Committee to Investigate Alleged Corruptions in Government: United States House Select Committee to Investigate Alleged Corruptions in Government
Document 9: J. William Fulbright: James William Fulbright (April 9, 1905 – February 9, 1995) was a United States Senator representing Arkansas from January 1945 until his resignation in December 1974. Fulbright is the longest serving chairman in the history of the Senate Foreign Relations Committee. A Southern Democrat and a staunch multilateralist who supported the creation of the United Nations, he was also a segregationist who signed the Southern Manifesto. Fulbright opposed McCarthyism and the House Un-American Activities Committee and later became known for his opposition to American involvement in the Vietnam War. His efforts to establish an international exchange program eventually resulted in the creation of a fellowship program which bears his name, the Fulbright Program.
Document 10: United States House Select Committee on an Alleged Abstraction of a Report from the Clerk's Office: United States House Select Committee on an Alleged Abstraction of a Report from the Clerk's Office
Document 11: Joseph McCarthy: Joseph Raymond McCarthy (November 14, 1908 – May 2, 1957) was an American politician who served as U.S. Senator from the state of Wisconsin from 1947 until his death in 1957. Beginning in 1950, McCarthy became the most visible public face of a period in the United States in which Cold War tensions fueled fears of widespread Communist subversion. He is known for alleging that numerous Communists and Soviet spies and sympathizers had infiltrated the United States federal government, universities, film industry, and elsewhere. Ultimately, the smear tactics he used led him to be censured by the U.S. Senate. The term "McCarthyism", coined in 1950 in reference to McCarthy's practices, was soon applied to similar anti-communist activities. Today, the term is used in reference to what are considered demagogic, reckless, and unsubstantiated accusations, as well as public attacks on the character or patriotism of political opponents.
Document 12: Cold War (1947–1953): The Cold War (1947–1953) is the period within the Cold War from the Truman Doctrine in 1947 to the conclusion of the Korean War in 1953. The Cold War began almost immediately following World War II and lasted through most of the 20th century. Political relations between the USA, Britain, Canada and the USSR were tainted within days of VJ-Day when cipher clerk Igor Gouzenko defected from the Soviet embassy in the Canadian capital, offering documentary proof of two wartime networks of Soviet spies in North America, one aimed at the Manhattan Project. In the next five years spies Julius and Ethel Rosenberg and Klaus Fuchs were exposed and British diplomats Guy Burgess and Donald Maclean defected to the Soviet Union.
Document 13: Blacklisted by History: Blacklisted by History: The Untold Story of Senator Joe McCarthy and His Fight Against America's Enemies, is a 2007 book by author M. Stanton Evans, who asserts that Joseph McCarthy was proper in making accusations of disloyalty, subversion, or treason within the US State Department and the US Army, showing proper regard for evidence (during a period in the late 1940s and 1950s known as McCarthyism or the second Red Scare).
Document 14: The Investigator: The Investigator (1954) was a radio play written by Reuben Ship and first broadcast by the Canadian Broadcasting Corporation (CBC) on May 30 of that year. The play lampooned the actions of the US House Committee on Un-American Activities (HUAC) and Senator Joseph McCarthy.
Document 15: Declaration of Conscience: The Declaration of Conscience was a speech made by U.S. Senator Margaret Chase Smith on June 1, 1950, less than four months after Senator Joe McCarthy's "Wheeling Speech," on February 9, 1950. Her speech was endorsed by six other liberal-to-moderate Republicans. In it, she criticized national leadership and called for the country, the United States Senate, and the Republican Party to re-examine the tactics used by the House Un-American Activities Committee (HUAC) and (without naming him) Senator Joe McCarthy. She stated the basic principles of "Americanism" were:
ground_truth: Joseph McCarthy