Continuity mistake: In the Episode "Sharif Returns" When Ducky shows Gibbs the eye in the gladd vial, it alternates between being completely submerged in the fluid to sticking out the top.
Yankee White - S1-E1
Deliberate mistake: Fornell doesn't recognize Gibbs, but subsequent episodes establish they have a long history together.
Continuity mistake: When Gibbs and the team meet the sheriff and ask to be shown the crime scene, he states that it was in the Edenvale motel room 8. In the opening scene the door that the gentleman knocked on and subsequently got his feet covered in blood from the body bleeding out was room 1. (00:00:50 - 00:04:05)
Continuity mistake: While Tony and Ziva are outside Ziva's hotel eating pizza, Ziva is eating the pizza in one shot with the slice in the shot, in the shot directly before this and directly after, the pizza is no where to be found and she is no longer chewing.
Character mistake: When Gibbs shows Major Dorden his badge, his ID card is upside down. (00:06:00)
Revealing mistake: When Kate is shot by Ari, Michael Weatherly flinches before the sound of the gunshot, in anticipation of the forthcoming squib explosion. (00:42:20)
Factual error: The commercial 747 landing in Washington from France is the president's plane Air Force One, not a regular passenger jet. It's actually reused footage from the film Air Force One.
Character mistake: Dr. Ducky mentions that the inventor of the guillotine in France was Dr. Joseph-Ignace Guillotin, but it was actually Dr. Antoine Louis.
Visible crew/equipment: While Gibbs is with Abby in the lab when she mentions her dissection of the laptop, in the overhead shot as Abby says, "since it came in here, Gibbs," the moving wheel of the camera dolly is visible at the bottom, right corner of the screen. (00:09:35)
Continuity mistake: When Tony spots Wilkerson's car in the mall's garage, in the first closeup of the Jetta the trunk has neither the Jetta badge nor the VW emblem, but in following shots both the Jetta badge and VW emblem are attached to the trunk. (00:14:55 - 00:16:55)
Continuity mistake: When Abby walks into the lab carrying the box with the Beretta Cougar she is barehanded, and two shots later she's wearing her latex gloves as she reaches for the bullet, but next shot she's barehanded again as she picks up the bullet to show Gibbs. Then, when Abby thanks Gibbs for getting her out of the sensitivity training, the latex gloves suddenly reappear, but they disappear in the next shot. (00:12:10)
Visible crew/equipment: While Ducky starts to tell Jimmy about an English earl, when Gibbs walks into Autopsy, the reflection of crew members are visible on the steel door's surface. (00:08:35)
Visible crew/equipment: When the "militia" guy fires the MP5 at the mannequin, after the last closeup of that mannequin it then cuts to a long shot facing the militia members, Gibbs, and Stone, and two crew members (one in shorts and the other wearing jeans) are visible at the top right side of the screen. (00:38:15)
Visible crew/equipment: When Tony tries to buy the sword for $500 the saleswoman walks away, and as he agrees to $600 in a following shot, the blue T-mark is visible on the floor. (00:23:10)
Factual error: The entire episode is contrived, as the Navy corpsman who is in legal trouble for rendering aid in an accident would not be in trouble due to the "good Samaritan law" in force in Virginia at the time.
Factual error: There is a big deal made about Gibbs giving Shepard one of his magazines in the study with La Granoille. It is implied that that magazine was used in the gun to kill La Granoille on his yacht. The magazine he gave her was for his department issued Sig Sauer P228, however, he was killed with a Glock 19. The magazines are not compatible.
Plot hole: We see Gibbs fire his sniper rifle and kill Saleem from a hill several hundred meters away over hilly and sandy terrain. We then see him shoot a guard while Tony and McGee are getting free. By the time they have walked down the corridor (about a minute) Gibbs has appeared in the hallway in full desert sniper suit. (00:40:00)
Character mistake: At the start, Kort takes the gun from one guy and uses it. He then places it at the second man's body without wiping it for prints. When he swaps his gun though, he wipes it for prints. Why didn't he wipe the first gun he used? (00:00:50)
Chosen answer: It is never stated, however she must have been there several years if she is on presidential detail.