Dempsey begins his third year as an assistant coach for the Saint Anselm men's lacrosse program in which he serves as the team's primary defensive coach. In addition to his duties with the Hawks, Dempsey is also currently serving at the headmaster at Nashua North High School.

Graduating from the University of New England in 1989 with a Bachelor's degree in Special Education, Dempsey also owns a Masters of Education degree from Rivier College, received in 2002. Dempsey was a three-year player during his time at UNE, including two years as a starter.

Dempsey's other coaching experience includes a nine-year stint as the assistant coach at Pinkerton Academy, during which the program captured eight state championships. He has coached the Nashua North girls team the last two years and is also the current president of the New Hampshire Youth Lacrosse Association (NHYLA).

Dempsey resides in Hooksett, N.H., with his wife, Donna, and his children, Ryan (14) and Hannah (9).