Welker passed the bar at age 21 and was elected as the prosecuting attorney for Washington County before he graduated. He was re-elected and served in that position from 1928 to 1936. Welker moved to Los Angeles in 1936 and had a private practice until 1943, when he enlisted in the U.S. Army Air Forces and served until 1944. He returned to Idaho and practiced law at Payette until 1950 and was a member of the state senate from 1949 to 1951.
U.S. Senate
In Idaho in 1950, Welker ran for the U.S. Senate. He won the Republican primary over Congressman John C. Sanborn and Governor C. A. Robins, and defeated former Democratic Senator D. Worth Clark in the general election. He gained seats on several important committees, including the Armed Services and Judiciary Committees. He soon distinguished himself as one of the most conservative and anticommunist senators, becoming a leading member and spokesperson for the right wing of the Republican Party.
In the early 1950s, Welker became closely associated with fellow Republican Senator Joseph McCarthy of Wisconsin and "McCarthyism", so much so that he was often referred to by Senate colleagues as "Little Joe from Idaho." In 1954, Welker was McCarthy's chief defender during censure proceedings in the U. S. Senate against McCarthy for the questionable investigative techniques McCarthy had used in pursuing individuals he accused of being communists, and others he accused of being homosexuals, within the government. Welker was one of 22 Republicans who voted against the censure of McCarthy in 1954 for these "red scare" communist witch hunts, and his so-called "lavender scare" tactics aimed at homosexuals in government. Welker, along with Republican Senator Styles Bridges of New Hampshire, was a key collaborator with McCarthy in the blackmail of Democratic Senator Lester C. Hunt of Wyoming and his son, that led to Hunt's suicide in his Senate office on June 19, 1954. Welker threatened Sen. Hunt, a staunch opponent of McCarthy's tactics, that if he did not immediately retire from the Senate and not seek re-election in 1954, Welker would see that his son's arrest for soliciting an undercover policeman was prosecuted and would widely publicize his son's alleged homosexuality. Welker also threatened Inspector Roy Blick of the Morals Division of the Washington Police Department with the loss of his job if he failed to prosecute Hunt Jr. After Hunt's suicide, a Republican, Edward D. Crippa, was appointed by the Republican acting governor of Wyoming, Clifford Joy Rogers, to fill the vacant seat. Alex Ross in The New Yorker wrote in 2012 of an event "loosely dramatized in the novel and film Advise & Consent Senator Lester Hunt, of Wyoming, killed himself after... Welker ... threatened to expose Hunt's son as a homosexual".
1956 election
In 1956, Welker ran for a second term in the Senate. Although he won the Republican nomination, again defeating Sanborn, he was decisively defeated by 32-year-old Democrat Frank Church of Boise; Welker gained less than 39 percent of the vote. This increased Democratic control of the Senate led to much anger within the Republican Party, with Joseph McCarthy even accusing President Dwight Eisenhower of not supporting Welker's reelection campaign enough.
Election results
Death
After leaving the Senate in January 1957, Welker practiced law in Boise and participated in farming. After a few months, however, he became ill, and traveled to Bethesda, Maryland, for medical treatment at the National Institutes of Health. He was admitted on October 16, 1957, where he was diagnosed with a brain tumor. Operations were quickly performed, but Welker died later that month at age 50. McCarthy had died earlier that year in Bethesda. Welker's funeral was at Fort Myer and he was interred in Arlington National Cemetery. He married Gladys Taylor Pence in 1930, and they had a daughter, Nancy.
