Dennis Webster DeConcini (; born May 8, 1937) is an American lawyer, philanthropist, politician and former Democratic U.S. Senator from Arizona. The son of former Arizona Supreme Court Judge Evo Anton DeConcini, he represented Arizona in the United States Senate from 1977 until 1995. After his re-election in 1988, no Arizona Democrats were elected to the United States Senate for 30 years until Kyrsten Sinema won his former seat in 2018. Background information DeConcini was born in Tucson, Arizona, the son of Ora (née Webster) and Evo Anton DeConcini. His father was judge on the Arizona State Superior Court for 10 years, then served as the Arizona Attorney General for one two-year term from 1948 to 1949 before being appointed to the Arizona State Supreme Court, where he served as a judge for four years, from 1949 to 1953. DeConcini received his bachelor's degree from the University of Arizona in 1959, and his LLB from the University of Arizona in 1963. He then worked as a lawyer for the Arizona Governor's staff from 1965 to 1967. DeConcini attended The JAG School at the University of Virginia and entered U.S. Army JAG Corps. Dennis DeConcini rejoined the law firm of DeConcini McDonald Yetwin and Lacy, which he and his father had co-founded in 1968, after leaving the Senate in 1995. He is a member of the advisory council of the Victims of Communism Memorial Foundation. Political career DeConcini served one elected term as Pima County, Arizona Attorney (1973–1976), the chief prosecutor and civil attorney for the county and school districts within the county. He was elected to the U.S. Senate in 1976 as a Democrat, defeated Republican Representative Sam Steiger for the open seat left by retiring Republican senator Paul Fannin. DeConcini served three terms in the Senate. Panama Canal DeConcini sponsored an amendment (the DeConcini Reservation) to the Panama Canal Treaty of 1977 which allows the United States "to take such steps as each [the U.S. or Panama] deems necessary, in accordance with its constitutional processes, including the use of military force in the Republic of Panama, to reopen the Canal or restore the operations of the Canal, as the case may be." Keating Five DeConcini was widely noted as a member of the Keating Five in a banking and political contribution ethics investigation during the 1980s which grew out of the U.S. Savings and Loan Crisis. The Senate investigation