Andrew Mahon graduated from Fordham University with a B.A. in History and French in 2002. He earned his J.D. in 2007 from Widener University School of Law, graduating with honors. He was a member of the Widener Law Journal. Between college and law school, he spent two years as an English teacher in France.

After law school, Mr. Mahon first worked as a law clerk for the Honorable Penny Blackwell in the York County Court of Common Pleas, then as a staff attorney for the Pennsylvania Immigration Resource (PIRC). As an attorney for PIRC, he represented individuals in removal proceedings who were most in need because of mental illness, past persecution, or poverty. 

He has been an attorney for the Law Office of Troy Mattes since 2010. He is admitted to practice in Pennsylvania, New Jersey, the U.S. District Court for the Middle District of Pennsylvania, and the U.S. Court of Appeals for the Third Circuit. He is also a member of the American Immigration Lawyers Association.