Lieutenant Commander Jack Reese works as a naval submarine officer and is assigned to the White House shortly after the 2002 election.
Formerly a regional officer for the Joint Chiefs of Staff, Reese serves the Bartlet Administration as military aide to National Security Adviser Nancy McNally. A Republican, Reese was first encountered outside a D.C. polling place, where Donna (who had realized too late that she had mismarked her absentee ballot for Rob Ritchie instead of President Bartlet) had been trying all day to find a Republican willing to swap votes with her. Reese trusted her enough to cast his ballot for Bartlet, so Donna would not feel like her vote was wasted. Reese and Donna eventually started seeing each other, but their romance was short-lived: Reese was transferred to Italy after Chief of Staff Leo McGarry accidentally revealed to the Secretary of Defense that Reese had prepared a sensitive report without the Defense Department's knowledge.