In 1775, Benson was a member of the Provincial Congress, his first political office. Appointed the State's first Attorney General in 1777, he also served in the New York Assembly. George Washington named him a commissioner to coordinate the evacuation of Loyalists from New York City in 1783 and he was a member of the Continental Congress, 1784-1788.
With Alexander Hamilton, Benson represented New York at the Annapolis Convention of 1786, where he served as the Convention's secretary. Benson was a member of the 1788 New York State convention to ratify the United States Constitution and served in the United States House of Representatives in the first and second Congress.
Egbert Benson was appointed an Associate Justice of the New York Supreme Court of Judicature in 1794. He wrote the majority opinion, in which Justices Radcliff, Kent and Lewis concurred, in the breach of promise case Johnson v. Caulkins. During the 1790s, when the frequent seizure of vessels bound for or sailing from New York caused the law of marine insurance to develop rapidly, Justice Benson was involved in many of the Court's ground-breaking decisions. As the sole dissenter in Sable v Hitchcock, 2 Johns. Cas. 79, N.Y.Sup. (1800), Benson refused to join the majority in creating an exception to the 1788 New York Anti-Slavery statute. Benson stated "there may be a sale of a slave, as a slave, and neither the seller be liable to the penalty, nor the slave be free, which is contrary to the express provision of the act."
Justice Benson resigned from the New York Supreme Court of Judicature when President John Adams appointed him to one of the federal circuit court judgeships established by the short-lived Judiciary Act of 1801. Judge Benson served on that court until it was abolished on July 1, 1802.
In 1804, Benson became the first president of the New York Historical Society, a position he held until 1816. Egbert Benson was elected to the House of Representatives of the Thirteenth Congress and served from March 4, 1813, to August 2, 1813.
When he resigned from Congress, Benson retired to Jamaica, Long Island, NY, where he died on August 24, 1833 at the age of 87. The Bensonhurst section of Brooklyn is named for his family.
James Kent. Egbert Benson, Associate Justice of the New York Supreme Court, 1794-1801
[Written by Chancellor Kent of New York, who studied law in Benson's law office. This biography was first published in Benjamin F. Thompson's History of Long Island, 1839].