Continuity mistake: Gibbs asks Abby what she has got for him. Abby lists all the stuff she has found and holds up the magazine with 2 hands. Camera cuts and now she is holding the magazine in one hand. (00:09:30)
Continuity mistake: When Tony and McGee drive off the rear window is half open. The camera shows the car driving away and the rear window is closed. (00:14:40)
Continuity mistake: When Tony and McGee are driving in the car near the start, Tony has a dark shirt on. As the car drives off his arm outside the window has a light coloured top on. (00:14:40)
Continuity mistake: When Gibbs is leaning on the desk talking about the beetle, he has his legs apart. Camera cuts and they are crossed. (00:17:20)
Continuity mistake: When Tony is eating the nuts, he holds the container near the top. Camera cuts and he holds it near the middle. (00:22:30)
Chosen answer: It is never stated, however she must have been there several years if she is on presidential detail.