Continuity mistake: When Kate and Gibbs are driving in the car, Kate's laptop is either on or off depending on the shot. (00:31:00)
The Truth Is Out There - S1-E17
Continuity mistake: When walking down the alley at the start their position is constantly changing forward and back. Note the new cement patch. (00:02:00)
Continuity mistake: At the naval base Gibbs is talking about the Marine taking his bike up into the mountains and blasting country music. The person he is talking to has their arms down by their side until the camera changes. They are then behind his back. (00:22:00)
Continuity mistake: When walking down the stairs at NCIS discussing the feather, the evidence bag Kate has switches hands instantly for a couple of seconds. (00:28:30)
Marine Down - S1-E9
Continuity mistake: After speaking with the colonel about the incident, we see an aerial shot of the colonel and a marine walking off, leaving the 3 NCIS agents on their own with no-one behind them. As the agents start walking a marine appears behind them. (00:09:00)
Marine Down - S1-E9
Continuity mistake: When Gibbs tapes Kate's palm pilot to the target it hangs vertically. Camera changes and now it is hanging horizontally. (00:03:15)
Continuity mistake: When DiNozzo rings Gibbs, we can see Kate taking metal scrapings on a pole that has tape on it just above her hands. When we get a closeup of Kate, the tape is not there. (00:25:50)
Continuity mistake: When the lady at the base exchange is throwing stuff at Tony, Tony has a yellow shirt in his hands that disappears, only to be thrown again. (00:24:00)
Continuity mistake: At the end the little boy tells Gibbs the password he has chosen for his tree house. As he does, Gibbs is working on the railing at the opposite end to the ladder. Gibbs says it's a good password and to come up. However he is now at the end of the railing by the ladder. (00:39:50)
Continuity mistake: At the very end we see Gibbs working on the treehouse. As the little boy climbs the ladder, Gibbs is working on a railing. Camera changes and now he is stepped back from the railing. (00:42:00)
Continuity mistake: When DiNozzo is reading the ingredients of the brass stripper, he has 2 hands on the tin in one shot and just 1 hand in the next. (00:29:00)
Yankee White - S1-E1
Continuity mistake: When Caitlin leaves the Cafe, Tim holds the car door open for her and she gets in. He then closes the door and leans on it. Camera cuts to a different angle and now he is stood up straight and slightly back from the car, with no time to do so. (00:29:05)
Yankee White - S1-E1
Continuity mistake: Just after Gibbs lies down on the slab, we see a shot of Ducky smirking. In this shot, we see Gibbs in the background turn on to his side. Camera changes to Gibbs and he is on his back and then turns onto his side. (00:24:00)
Chosen answer: It is never stated, however she must have been there several years if she is on presidential detail.