Continuity mistake: When the victim falls to the ground in the pre-title sequence his eyes are closed and a pool of blood spills onto the floor from his mouth. When Tony and Ziva are examining the body and taking photo's of the victim, his eyes are now open and the pool of blood is gone from by his mouth. (00:00:50 - 00:03:10)
Safe Harbor - S9-E5
Continuity mistake: The way DiNozzo holds the little black book changes between shots when he is first examining it. (00:11:20)
Continuity mistake: The bottle of Pepto Bismol that Fornell places on the counter at the start simply vanishes from the shot. (00:04:05)
Continuity mistake: When Gibbs is looking at the photo of the Dog Tags in his basement, the way he holds the photo changes between shots. (00:19:20)
Continuity mistake: When Gibbs is talking to the chaplain about keeping daughters safe, the way he holds his coffee changes between shots. Note his grip on the cup. (00:23:00)
Continuity mistake: When we see young Gibbs sanding the birdhouse, the way he's holding the bird house changes between shots. It goes from being upright to on it's side. (00:35:30)
Continuity mistake: During their first day's investigation of the double homicide Tony is wearing a grey suit, white shirt, and burgundy tie. On the second day, while Tony is wearing a dark suit, light blue shirt and dark blue tie, when Gibbs tells Tony to go see what Ducky wants in Autopsy, Tony is back to wearing what he wore on their first day. Then at Tobett's house, Tony is again wearing the light blue shirt and dark blue tie. (00:04:30 - 00:31:00)
Continuity mistake: When DiNozzo has got the victims watch on, it's on over his white glove. When the shot changes it's now over his bare skin and not the glove. (00:10:20)
Continuity mistake: When Ziva dumps the four bundles of $100.00 bills on the bed, they all land face up. Then the scene changes to Tony taking a picture of them. Back to the bundles, and now only three are face up and one is face down, with no one touching them. (00:10:40)
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)
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)
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.