Teresa Bagioli Sickles (1836 – February 5, 1867) was the wife of Democratic New York State Assemblyman, U.S. Representative, and later U.S. Army Major General Daniel E. Sickles. She gained notoriety in 1859, when her husband murdered her lover, Philip Barton Key II, son of Francis Scott Key. At his trial, Sickles claimed for the first time in United States jurisprudence a defense by temporary insanity. He was acquitted. Early years Born in New York City in 1836, Teresa Da Ponte Bagioli was the daughter of the wealthy and well-known Italian singing teacher Antonio Bagioli (1795–1871) and his wife, Maria (or Eliza) Cooke (1819–1894). Maria was the adopted and alleged "natural" child of Lorenzo Da Ponte. During her youth, Teresa sometimes lived and studied in the household of her grandfather, Lorenzo da Ponte, the noted music teacher, who had worked as Mozart's librettist on such masterpieces as The Marriage of Figaro. An exceptionally bright child, she spoke five languages by the time she was a young adult. Da Ponte's son, a New York University professor, befriended the teenaged Dan Sickles and helped secure him a scholarship to the University. Young Sickles also moved into the Da Ponte home; he left after about a year when his mentor suddenly died but maintained close ties with the family, possibly to continue the study of French and Italian. Though Sickles had known Teresa since her infancy, he made her acquaintance again in 1851, this time as an Assemblyman. He was thirty-two years old, she was fifteen. Sickles, a notorious womanizer, was quite taken with Teresa and soon proposed marriage. Despite his prominence and long connection to the family, the Bagiolis refused to consent to the marriage. Undeterred, the couple wed on September 17, 1852, in a civil ceremony. Teresa's family relented and the couple married again, this time with John Hughes, Catholic Archbishop of New York City, presiding. Some seven months later in 1853, their only child Laura Buchanan Sickles was born. New York and Washington society In 1853, Sickles became corporation counsel of New York City, but soon resigned to serve as secretary of the U.S. legation in London under James Buchanan, by appointment of President Franklin Pierce. One source alleges he took a prostitute named Fanny White with him on his overseas assignment, while another source reports that he sent for Teresa after a few months. In any case, he returned