As has been discussed many times in these pages, the Fourth Amendment secures the right to be free of searches absent a warrant establishing probable cause. A law enforcement search without probable cause is unlawful. …Or so they say.
Over the years, many exceptions to this right have been carved out. One exception to the Fourth Amendment is vehicle searches. While probable cause to search a vehicle is nominally still in effect, the threshold is lower. Warrantless searches of a vehicle and contents therein may be searched if a law enforcement officer can establish probable cause that some sort of criminal activity is afoot. (Other exceptions apply, such as consent to search and a search incident to arrest, but here we will discuss a search of a vehicle based on probable cause.) Under the automobile exception, a search of a vehicle is lawful if the search is based on facts that would otherwise justify the issuance of a search warrant. The courts have found probable cause to search a vehicle based on ambiguous facts, such as the officer observed the driver or passengers making furtive movements, or the nervousness of the driver coupled with other observations.
But how far can the search go? Recently, the California Court of Appeals held that officers cannot search the trunk of a vehicle if the search was conducted on probable cause that contraband or evidence was located in the passenger portion of the vehicle. The case, People v. Leal (2023) 93 Cal. App. 5th 1143 binds officers to a probable cause search only to those portions of a vehicle where facts observed or known to officers justify the search.