From July 2005 through June 2006, he was the Acting Dean of the School of Music, and he was Deputy Dean from 1997 to 2005. He received his Bachelor of Science in Music Education (magna cum laude) and Master of Musical Arts in Composition from the University of Connecticut, and his Doctor of Musical Arts in Composition from Cornell University, where he studied with Karel Husa and Steven Stucky. He has taught music courses at the Hartford Conservatory, the University of Connecticut, the Auburn Maximum Security Correctional Facility, Cornell University, and Yale University.
Duffy served as President of the College Band Directors National Association from 2009 to 2011. His music is published by American Composers Alliance, Ludwig Music and Bourne Company Music Publishers. In 1996, Dr. Duffy was selected as Outstanding Music Educator of the Year by the Connecticut Music Educators Association.