Continuity mistake: When Tony and Ziva discover the hiding place of Amanda, the position of the dead body's extended hand and the puddle of blood change. (00:13:40)
Agent Afloat - S6-E2
Continuity mistake: During the investigation of the dead wife's crime scene, the arms of the corpse change position from shot to shot throughout the scene, including a moment where the corpse's arms are crossed, then in the next shot Ducky is shown crossing her arms. Ducky is also shown crossing the same arm twice, and the guitar control also changes direction and position with respect to the body. (00:03:20 - 00:05:30)
Continuity mistake: During the conversation between Jackson and Ziva, a $20 bill is dropped, face down. When Ziva bends down to pick it up, the bill is now face up.
Agent Afloat - S6-E2
Continuity mistake: Near the end, several of the items on Ziva's desk change orientation from one shot to the next.
Murder 2.0 - S6-E6
Continuity mistake: When NCIS catches the killer, the way he holds a dead man's switch changes. In some shots, he holds it with all five fingers, and in others he holds it with his middle two fingers and thumb, with his index and pinkie fingers extended. (00:39:45)
Nine Lives - S6-E5
Continuity mistake: When Fornell walks past the reporters at the court house he passes The Wall. Camera cuts and he has jumped back and isn't near The Wall. (00:36:30)
Continuity mistake: When Vance shows Gibbs the access card belonging to their dead petty officer, the position of his hand on the card changes between shots. (00:38:35)
Continuity mistake: 6.17 - South by Southwest. The first time Tony is talking on the phone to London about his uncle's estate, he is alternately either talking on his cellphone or office phone throughout the conversation. (00:06:15)
Continuity mistake: Episode "Heartland": In the first five minutes of the show, after the guys are beaten up in the alley, when the black guy is laid down on the ground there is a blood stain on The Wall, behind where he was standing. When the other guys go to the white guy's aid the blood stain is gone, for about 3-4 shots. When the NCIS team is there gathering evidence the blood is back on The Wall.
Chosen answer: It is never stated, however she must have been there several years if she is on presidential detail.