Clayton "Clay" Jarvis was a politician and also Secretary of the Navy or SECNAV.
NCIS Season 8
NCIS Season 9
NCIS Season 10
NCIS Season 11
- Jarvis is also the first SECNAV in the entire NCIS series to have been killed in the line of duty as all his fellow predecessors presumably either retired or subsequently resigned from their position as SECNAV.