American attorney and politician who was a longtime member of the U.S. Senate (Senate) (1989– ). Elected originally as a Democrat (Democratic Party), he won reelection in 2006 as an independent after losing the Democratic Party primary. In 2000 he was the Democratic vice presidential nominee—the first Jewish candidate on a major party presidential ticket.

Lieberman studied at Yale University, where he earned both a B.A. (1964) and LL.B. (1967). During the 1960s he was active in the civil rights movement and briefly practiced law. In 1970 (in a campaign in which future U.S. Pres. Bill Clinton (Clinton, Bill), then a student at Yale, served as a volunteer) Lieberman was elected to the Connecticut Senate, and he was majority leader from 1975 to 1981. In 1980 he was defeated in a bid for a seat in the U.S. House of Representatives (Representatives, House of), but two years later he was elected Connecticut attorney general. In 1988 he won election to the U.S. Senate, becoming the first Orthodox Jew to sit in that body, and he was reelected in 1994. Lieberman, who served as the chairman of the Democratic Leadership Council, took a generally centrist stance. Although he supported Democratic positions on issues such as campaign finance reform, abortion rights, and gun control, he broke ranks with his party by advocating school vouchers, cuts in capital gains taxes, and limits on liability awards.

In 2000 Lieberman was chosen by Al Gore (Gore, Al), the Democratic presidential candidate, to be his running mate. The decision was seen as a bold one, but it was met with widespread approval. Lieberman's religious beliefs had a pervasive influence on his life and work, and he was the first Jewish candidate on a national ticket of a major U.S. political party. He had been the first Democratic senator to publicly criticize President Clinton (Clinton, Bill) for his behaviour in the Monica Lewinsky affair—in which Clinton first denied and then admitted having had a sexual relationship with a White House intern—although he later voted against removing Clinton from office. It was thought that one of the benefits of Lieberman's candidacy would be to help distance the Democratic ticket from the scandals of the Clinton administration. Although Gore and Lieberman won more popular votes than their Republican opponents (George W. Bush (Bush, George W.) and Dick Cheney (Cheney, Dick)), they were narrowly defeated (271–266) in the electoral college. Lieberman, however, had also appeared on the Connecticut ballot for reelection to the Senate, a contest he won easily.

In January 2003 Lieberman announced his intention to run for the Democratic nomination for the 2004 presidential election. He failed to garner the endorsement of Gore, and many Democrats questioned his support of the Iraq War. After losing the New Hampshire primary in February 2004, he withdrew from the race.

Lieberman's position on the war proved particularly problematic during his 2006 Senate reelection, at a time when many Democrats were becoming increasingly frustrated by the Bush administration's handling of the war. Running against him in the Democratic primary was the relatively unknown antiwar candidate Ned Lamont, who narrowly defeated the incumbent. In response, Lieberman announced that he would continue in the race as an independent (or, as he phrased it, an “independent Democrat”) and defeated Lamont in the election by a comfortable margin. Though elected as an independent, Lieberman opted to caucus with the Democrats—thus helping them secure a tenuous majority—and became chairman of the Senate Committee on Homeland Security and Governmental Affairs. However, Lieberman continued to roil Democrats, endorsing Republican John McCain (McCain, John) for president in 2008 and criticizing the Democratic nominee, Barack Obama (Obama, Barack). In November 2008, shortly after Obama won the presidential election, the Democratic caucus approved a resolution that condemned campaign comments made by Lieberman and removed him as chairman of an Environmental and Public Works subcommittee. However, he was allowed to continue as head of the powerful Senate Committee on Homeland Security and Governmental Affairs.

Lieberman is the author of numerous books, including the memoir In Praise of Public Life (2000; with Michael D'Orso) and, with his wife, Hadassah, An Amazing Adventure: Joe and Hadassah's Personal Notes on the 2000 campaign (2003; with Sarah Crichton).