He was elected to the United States House of Representatives from Pennsylvania's 2nd congressional district and served from 1799 to 1803.

[2] From 1805 to 1809, a power struggle ensued in the Pennsylvania Republican Party with Leib and William J. Duane on one side and Simon Snyder on the other.

Leib was elected to the term beginning on March 4, 1809, but assumed office on January 9, 1809, following the resignation of Samuel Maclay.

He became prothonotary of the United States district court in Philadelphia in November 1822 and served in that role until his death in December 1822.

[2] In 1924, he was reinterred to the Laurel Hill Cemetery in Philadelphia when the church and burial ground were demolished during the construction of the Benjamin Franklin Bridge.

[10] This article incorporates public domain material from the Biographical Directory of the United States Congress