Once a Hero - S4-E8
Revealing mistake: When Ducky opens the fridge door containing the suspected killer, the dead body's eye twitches. (00:21:00)
Once a Hero - S4-E8
Other mistake: When Abby is talking to the microscope guy during the line "you understand without having to go find a dictionary" there is a half second flash of another shot with DiNozzo walking off camera in a street setting. Maybe just a encoding error on Netflix but it persisted after reloading. (00:23:45)
Once a Hero - S4-E8
Audio problem: When the director is working out the letters on The Wall in the video feed her mouth doesn't move for the last L but her voice is heard. (00:38:20)
Once a Hero - S4-E8
Continuity mistake: When DiNozzo is resting at his desk, he has he feet crossed with his left foot on top of his right foot. When the shot changes his right foot is now on top. His hands have also gone from clenched to unclenched in the same shots. (00:20:25)
Once a Hero - S4-E8
Revealing mistake: When we see Ziva having a close up look at the dead girl, the dead girl's eyes twitch and move slightly. (00:09:20)
Once a Hero - S4-E8
Continuity mistake: The way Gibbs holds his ID out to the maintenance man changes between shots. In the first shot he has 2 fingers inside the ID in the second shot just his thumb is inside the ID. (00:07:40)
Once a Hero - S4-E8
Other mistake: Ducky states that the Bronze Star was for Valor. However, the bronze V that signifies the star was for Valor is not present. There is no way Ducky could know it was for Valor. (00:05:20)
Once a Hero - S4-E8
Continuity mistake: When talking to Luis, his ID badge keeps moving and rotating without touching it. (00:08:20)
Once a Hero - S4-E8
Revealing mistake: When Ducky and Gibbs are in the morgue examining the body of the girl found in the hotel, the camera cuts for a few seconds to the girl lying on the slab. During that shot, you can see her neck moving to her pulse (just after Ducky says, "There's some bruising on the sternum"). (00:19:10)
Chosen answer: It is never stated, however she must have been there several years if she is on presidential detail.