Nicholas "Doc" Perna is a former 82nd Airborne officer and longtime police officer. He's an EMT and Street Crimes supervisor who has over the course of his career served in just about every possible billet: patrol, detectives,  counter-narcotics, gang task force, SWAT, and others. He's a firearms instructor and Terrorism Liaison Officer and has been decorated for valor in the line of duty by his department. A combat veteran of Iraq, he has conducted psychological operations as part of Joint Special Operations Task Force Arabian Peninsula, also filling such other billets as airborne medical platoon leader, company commander, battalion intelligence officer, and battalion OPSO.