Clements became Member of Parliament (MP) for Duleek in 1727 under the patronage of Luke Gardiner, a powerful political and business figure in Dublin.
He became the main financial manager of the British and Irish Government in Ireland during the period, and was de facto Minister for Finance from 1740 to 1777.
In 1776, Clements stood for again for Cavan Borough as well as Carrick and represented the latter constituency until his death in 1777.
He was a developer of property in Georgian Dublin, including part of Henrietta Street where he lived at No.
[2] He was one of the richest commoners in Ireland, notwithstanding his involvement in a failed banking venture in 1759.