[citation needed] He moved to Poultney, Vermont, where he studied law and was admitted to the bar.

Mallary was elected trustee of the Rutland County Grammar School in 1807.

As a Democratic-Republican, Mallary successfully contested the election of Orsamus C. Merrill to the Sixteenth Congress.

He was reelected as an Anti-Jacksonian candidate to the Twenty-first and Twenty-second Congresses, serving from January 13, 1820, until his death in Baltimore, Maryland, on April 15, 1831.

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