No Vacancy - S17-E7
Factual error: While investigating a Marine's murder, the team uncovers a labyrinth of live-streaming spy cameras hidden in the rooms of a Virginia motel. They show an attic in a motel room with cameras in multiple vents, the problem is that there are no air duct tubes which those cameras should have been mounted in. With no duct work you have no heat or no A/C, all you get is dust.
Chosen answer: "Policing your brass", means to pick up your expended shell casings, after firing your rifle, or pistol.
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