Ingersoll affiliated with the Federalist Party and was deeply disturbed by Thomas Jefferson's victory in the 1800 presidential election.

[1] His major contribution to the cause of constitutional government came not during the convention but later during a lengthy and distinguished legal career when he helped define many of the principles enunciated at Philadelphia.

[5] He wrote an account of Isaac Barre's speech[6] made during the Parliamentary debate on the Stamp Act to Connecticut Governor Thomas Fitch.

[1][7] The younger Ingersoll completed Hopkins Grammar School in New Haven in 1762,[8] graduated from Yale College in 1766, studied law in Philadelphia, and was admitted to the Pennsylvania bar in 1773.

[9][10] Although by training and inclination a Patriot sympathizer, the young Ingersoll shied away from the cause at the outset because of a strong sense of personal loyalty to his distinguished father.

On his father's advice, he sought to escape the growing political controversy at home by retiring to London to continue his study of the law at the Middle Temple School (1773–1776) and to tour extensively through Europe.

With the help of influential friends he quickly established a flourishing law practice, and shortly after he entered the fray as a delegate to the Continental Congress (1780–81).

[10][12] Always a supporter of strong central authority in political affairs, he became a leading agitator for reforming the national government in the postwar years, preaching the need for change to his friends in Congress and to the legal community.

At the convention, Ingersoll was counted among those who favored revision of the existing Articles of Confederation, but in the end he joined with the majority and supported a plan for a new federal government.

Ingersoll's major contribution to the cause of constitutional government came not during the convention but later during a lengthy and distinguished legal career, when he helped define many of the principles enunciated at Philadelphia.

[3] Ingersoll also served as counsel in various cases that helped clarify constitutional issues concerning the jurisdiction of federal courts and U.S. relations with other sovereign nations, including defending Senator William Blount of Tennessee against impeachment.