Police arrested 22-year-old Christopher Nixon and 18-year-old James Nixon on Monday in the killing in a park in New Castle. It wasn't immediately clear if the men are related.
Investigators say the men killed Marcus McCauley on Saturday in Gaston Park. He was found shot in the head near a pavilion.
Christopher Nixon denied wrongdoing after following his arraignment.
Online court records do not list attorneys for either suspect. They are both being held without bail at Lawrence County Prison.