He was born in Boston, Massachusetts and attended Boston Latin School. He graduated from Harvard College in 1749, then taught school and studied theology. He became a merchant marine and traveled to the southern colonies, Spain, the Azores, and England. He returned home, and was admitted to the bar of Massachusetts in 1757, practicing in Portland, then part of Massachusetts (but now in Maine), and later in Taunton, Massachusetts. Paine was associate prosecuting attorney in the trials of British soldiers following the Boston Massacre.
He was elected to the Provincial Assembly in 1770, and selected in 1774 to attend the first Continental Congress, where he helped frame the rules of debate and helped acquire gunpowder for the coming war. He signed the final appeal to the king (the Olive Branch Petition) in 1775. He represented Massachusetts at the Continental Congress of 1776.
In 1777 he was elected attorney general of the state of Massachusetts. He was appointed to the Supreme Court in 1796, served fourteen years, and retired, dying at the age of eighty-three.