Warrantless rental car searches

1. Whether the Fourth Amendment's plain view doctrine permits a warrantless search of a rental vehicle with expired registration based on an officer's subjective claim that white powder has a "bluish tint" indicating cocaine, when the alleged tint is not visible on body camera footage, the officer admits he has conducted no scientific testing to verify his identification method, and the rental vehicle context means the substance could have been left by any previous renter. 2. Whether probable cause exists under the automobile exception to the Fourth Amendment's warrant requirement when based on the combination of: (1) a rental vehicle with expired vehicle registration justifying the initial stop; (2) travel on a highway characterized as a drug corridor; (3) a multi-day trip without visible luggage; (4) alleged white powder with a subjective "bluish tint" not clearly visible on video; and (5) a faulty field test conducted with a kit that the officer admittedly destroyed at his post following the traffic stop, eliminating the possibility of independent verification of the test's reliability or results and violating the defendant's due process right to examine and challenge the evidence.