Visible crew/equipment: Gibbs walks into Abby's lab while she's resting under the desk, and when Gibbs helps Abby stand up the bouncing shadow of the boom mic/pole is visible at the top, right side of the screen. (00:26:20)
The Missionary Position - S9-E20
Continuity mistake: When Ziva and Monique confront the two CIA agents in the car, the woman's hand keeps alternating from on the wheel to off the wheel. (00:36:00)
Factual error: The ferry carrying Ziva and Tony to the aircraft carrier should have the Italian merchant flag, but it has the national one (this flag hasn't got the shield drawn in the middle).
Continuity mistake: When Tony & Ziva meet their contact in Naples, we see a local cop walking down the background behind them, and passing a walkway to the boat. Seconds later, as the camera changes view, we see that cop about 30 feet back, going the same way.
Up in Smoke - S9-E23
Continuity mistake: When we see Gibbs and Dr. Ryan at Gibbs' house he places two mugs on the table. The mugs' positions change between shots. (00:16:10)
Up in Smoke - S9-E23
Continuity mistake: When Dr Ryan holds out her hand for the file from Gibbs at his house, the hand she holds out switches between shots. (00:17:40)
Up in Smoke - S9-E23
Visible crew/equipment: When Ziva walks into the interrogation room after the sting, the camera and operator is visible in the mirror. (00:34:30)
Till Death Do Us Part - S9-E24
Visible crew/equipment: When Dr Ryan is talking to Vance, a light screen is reflected in her sunglasses. (00:04:30)
Till Death Do Us Part - S9-E24
Continuity mistake: The way Ducky passes Jimmy the organs from the cadaver, the way he holds them changes between shots. (00:06:10)
Chosen answer: It is never stated, however she must have been there several years if she is on presidential detail.