Question: Why was Chip framing Dinozzo for the murder of the unidentified woman?
Answer: Because Chip made a lab error in a previous job, and Abby and Dinozzo were instrumental in revealing/correcting the mistake which got Chip fired. Hence the grudge against Dinozzo and Abby. So, he framed Dinozzo for a murder and attempted to kill Abby at the end of the show.
Answer: He was only after DiNozzo. He only tried to kill Abby because she found him out and got too close.
Chosen answer: "Policing your brass", means to pick up your expended shell casings, after firing your rifle, or pistol.
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