A member of the Republican Party, he previously served as York County district attorney from 2018 to 2025.

He enrolled at Harrisburg Area Community College, but dropped out to enlist in the United States Navy,[2] and he served from 1995 to 1999.

He began his legal career as a law clerk for a judge in the York County Court of Common Pleas.

[5] In 2013, the U.S. Department of Justice appointed Sunday as a special assistant U.S. attorney for the Middle District of Pennsylvania.

Sunday won the 2017 election to serve as district attorney of York County,[5] and took office in January 2018.