David C. Broderick was born in 1820 in Washington, D.C., blocks from the Capitol, where his Irish immigrant father worked as a stonecutter. The family moved to New York City around 1823, and Broderick apprenticed as a stonecutter before rising in the city’s Democratic ward politics. In 1846 he won the Democratic nomination for New York’s fifth congressional district but took only about 38 percent against his Whig opponent. He moved to Gold Rush California, reached the new state senate by 1850, served as its president in 1851 and 1852, and briefly became acting lieutenant governor.

In San Francisco his machine controlled the ballots and polling places, and he required officeholders whose posts earned fees of up to $50,000 a year to kick back half to him. The legislature sent him to the U.S. Senate in 1857, where he led California’s free soil Democrats against the pro-slavery faction. His friendship with Chief Justice David S. Terry collapsed after Terry lost reelection and blamed him; Broderick called Terry a miserable damned wretch and compared him to President James Buchanan. On September 13, 1859, at Lake Merced, Broderick’s hair trigger pistol fired into the ground and Terry shot him in the right lung; he died on September 16.

• He remains the only sitting U.S. senator killed in a duel.
• Edward Dickinson Baker’s eulogy recast the duel as a political assassination by pro-slavery forces.
• His portrait hung at the May 1860 Republican National Convention in Chicago that nominated Abraham Lincoln.
• He was buried at Lone Mountain Cemetery and moved decades later to Colma.
• In 1889 deputy marshal David Neagle shot Terry dead after Terry assaulted Justice Stephen Johnson Field, an old Broderick ally, on a California train.