Continuity mistake: We see Fornell handing Gibbs a beer at his house and his phone is in his right hand. When the shot changes, his phone is now in his left hand. (00:10:40)
The Missionary Position - S9-E20
Continuity mistake: When Ziva and Monique confront the two CIA agents in the car, the woman's hand keeps alternating from on the wheel to off the wheel. (00:36:00)
Till Death Do Us Part - S9-E24
Visible crew/equipment: When Dr Ryan is talking to Vance, a light screen is reflected in her sunglasses. (00:04:30)
Lost at Sea - S10-E4
Continuity mistake: When Gibbs pulls the empty bottles out of the evidence box, he pulls three out and places them on the desk. However, when the camera changes to behind Gibbs, there are only two bottles on the desk. (00:24:10)
Visible crew/equipment: At the naval yard when Ducky is exiting the cab, as it drives off you can see an orange tape marker on the floor. (00:24:30)
Up in Smoke - S9-E23
Visible crew/equipment: When Ziva walks into the interrogation room after the sting, the camera and operator is visible in the mirror. (00:34:30)
Up in Smoke - S9-E23
Continuity mistake: When Dr Ryan holds out her hand for the file from Gibbs at his house, the hand she holds out switches between shots. (00:17:40)
Visible crew/equipment: Gibbs walks into Abby's lab while she's resting under the desk, and when Gibbs helps Abby stand up the bouncing shadow of the boom mic/pole is visible at the top, right side of the screen. (00:26:20)
Visible crew/equipment: When Ziva and Tony arrive at the crime scene, a visible marker is on the floor exactly where McGee comes to stand. (00:03:50)
You Better Watch Out - S10-E10
Other mistake: McGee's text to Tony says "Dell's body found. Rock Creek Park." The suspect they are looking for and body found is named Justin Cannady. (00:22:23)
Revealing mistake: When Gibbs' flip phone started ringing, and he flipped it open to answer it, for the brief second, in the closeup shot of the flip phone, the screen on the phone says "No Service" despite receiving an incoming call.
Chosen answer: It is never stated, however she must have been there several years if she is on presidential detail.