Season 11, Episode 8 is titled " Concrete Alibi ," detailing the real-life murder of Karyn Slover.
A defense attorney approaches Gibbs with information protected by attorney-client privilege, suggesting her client—who was being investigated for a different crime—was actually at the scene of the Marine's death.
If you are looking for a different series, "Alibi" or similar titles appear in other Season 11 lineups:
The story focuses on the NCIS team reopening a hit-and-run case involving a Marine's death after a lawyer, Carrie Clark (played by Salli Richardson-Whitfield ), provides information that her client has a solid alibi for another crime that inadvertently links him to the murder.