Education
He studied law and was admitted to the bar in 1760.
He studied law and was admitted to the bar in 1760.
Following his tenure in the Senate, he served in the Pennsylvania House of Representatives on two separate occasions, as a county judge, and as a presidential elector. Maclay pursued classical studies, and then served as a lieutenant in an expedition to Fort Duquesne in 1758. He went on to serve in other expeditions in the French and Indian Wars.
After a period of practicing law he became a surveyor in the employ of the Penn family, and then a prothonotary and clerk of the courts of Northumberland County in the 1770s.
During the American revolution he served in the Continental Army as a commissary. After the ratification of the Constitution Maclay was elected to the United States Senate and served from March 4, 1789 to March 4, 1791.
He received a two-year term instead of the usual six-year term for senators after he lost a lottery with the other Pennsylvania senator, Robert Morris. In his journal, which is the only diary and one of the most important records of the First United States Congress, he criticizes John Adams and George Washington.
He also criticized many of their supporters who ran the senate and included particularly senators, believing that their ways of running the Senate were inefficient.
He was unsuccessful in his attempt to be re-elected by the state legislature of Pennsylvania. In addition, he was a presidential elector in 1796, a county judge from 1801 until 1803, and a member again of the State house of representatives in 1803. He later died in 1804 and was interred in Old Paxtang Church Cemetery in Harrisburg.
Maclay, along with Robert Morris, was a member of Pennsylvania"s first two-member delegation to the United States Senate. He was also a frequent member of the State legislature in the 1780s. During that period he was also the Indian commissioner, a judge of the court of common pleas, and a member of the executive council.
In the Senate, Maclay was one of the most radical members of the Anti-Administration faction.
Maclay retired to his farm in Dauphin, Pennsylvania, but was also a member of the Pennsylvania State House of Representatives in 1795, 1796 and 1797.
