David was born in 1969 and raised in Pickens by his parents, Bob and Bert Allison, both schoolteachers.  He graduated from Pickens High in 1987, Erskine College in 1991, and the University of South Carolina law school in 1995.  He practiced law in Pickens County from 1995 until 2018.  He began working in his current position in January of 2019.

David has a younger brother, Mark, who is an attorney with the Greenville office of McAngus Goudelock & Courie.  David has one daughter, Sarah.