Admitted to Middle Temple, London, England. Admitted to Philadelphia bar, 1757. Member Assembly of Lower Counties (Delaware), 1760, later became speaker.
Member Pennsylvania Legislature from Philadelphia, 1762-1764, 70-76. Printed pamphlet The Late Regulations Respecting the British Colonies on the Continent of America Considered, 1765. Delegate to Stamp Act Congress from Pennsylvania, 1765.
Chairman Committee of Correspondence, 1774. Member Continental Congress, 1774-1776, 79-81. Chairman of a committee of safety and defense, 1775.
Advocated conciliation with England. Voted against Declaration of Independence. Colonel 1st Battalion raised in Philadelphia.
President Supreme Council Delaware, 1781. President Supreme Council Pennsylvania, 1782-1785. Delegate United States Constitutional Convention from Delaware, 1787.
Noted for published series of letters urging adoption of Constitution, signed Fabius. Author: Letters from a Farmer in Pennsylvania to the Inhabitants of the British Colonies (urged non-importation instead of violence), 1768.