Q. Can the police search my car without a warrant?
A. Yes, if the car is readily mobile and there is probable cause.
The United States Supreme Court answered this question in Md. v. Dyson, 527 U.S. 465, 466-467 (1999). It stated
The Fourth Amendment generally requires police to secure a warrant before conducting a search. California v. Carney, 471 U.S. 386, 390-391, 85 L. Ed. 2d 406, 105 S. Ct. 2066 (1985). As we recognized nearly 75 years ago in Carroll v. United States, 267 U.S. 132, 153, 69 L. Ed. 543, 45 S. Ct. 280 (1925), there is an exception to this requirement for searches of vehicles. And under our established precedent, the “automobile exception” has no separate exigency requirement. We made this clear in United States v. Ross, 456 U.S. 798, 809, 72 L. Ed. 2d 572, 102 S. Ct. 2157 (1982), when we said that in cases where there was probable cause to search a vehicle “a search is not unreasonable if based on facts that would justify the issuance of a warrant, even though a warrant has not been actually obtained.” (Emphasis added.) In a case with virtually identical facts to this one (even down to the bag of cocaine in the trunk of the car), Pennsylvania v. Labron, 518 U.S. 938, 135 L. Ed. 2d 1031, 116 S. Ct. 2485 (1996) (per curiam), we repeated that the automobile exception does not have a separate exigency requirement: “If a car is readily mobile and probable cause exists to believe it contains contraband, the Fourth Amendment . . . permits police to search the vehicle without more.” Id. at 940.
Md. v. Dyson, 527 U.S. 465, 466-467 (U.S. 1999)