Written by attorney Marc G. Beginin

When Can a Police Officer Stop and Search Your Car?

The Fourth Amendment to the U.S. Constitution protects against unreasonable searches and seizures. Generally a warrant for arrest, issued by a magistrate and supported by probable cause, is required for a search and seizure. However, there are numerous exceptions to this rule, especially in the context of automobile searches.


Traffic Stops. Simple traffic violations have become the downfall of many drug dealers, getaway drivers and fugitives. By failing to observe basic traffic laws, including speeding, rolling through stop signs, failing to use turn signals and a seemingly innumerable other moving violations, law enforcement is given a reason on a silver platter to investigate beyond the scope of the initial stop.

An officer that pulls you over has the opportunity to interact with you. While the stop may be a pretext to question you, if in fact the officer observed a traffic infraction, the officer may make the stop irregardless of the alternative reason for making the stop. However, the officer cannot selectively enforce a traffic law (e.g., based on racial profiling), which may be deemed to deny one equal protection under the Fourteenth Amendment, as a pretext for the stop.

Investigative Stops. An officer who suspects that a driver is engaged in criminal activity may lack probable cause for an arrest, but it may be enough to engage in what is known as an "investigative stop". For example, the police may have received a credible tip that a drug deal is about to occur, or someone is transporting contraband in a vehicle. Even if the officer lacks probable cause to arrest or search the motorist, the officer can stop and temporarily detain the motorist to investigate further if "there is articulable suspicion that a person has committed or is about to commit a crime." Terry v Ohio, 392 US 1 (1968).


If the initial traffic stop was legal, either because of valid stop based on a traffic infraction or because of reasonable suspicion for the stop, then the next question to address is whether the officer exceeded the scope of the stop.

For a stop based on a simple traffic violation, "once the driver has demonstrated that he is entitled to operate his vehicle, and the police officer has issued the requisite warning or ticket, the driver ‘must be allowed to proceed on his way.’ " United States v Branch, 537 F3d 328, 336 (4th Cir 2008). Therefore, the officer cannot use a traffic stop to probe the motorist about unrelated matters if doing so expands the scope of the initial stop beyond the time that would otherwise be necessary to complete the stop.

However, the officer is not limited to asking a motorist for license and registration and may inquire about other topics. The officer is also not required to allow the driver to remain in the motor vehicle.

"A stop may be extended for a length of time sufficient to enable the apprehending officer to ask the driver to step out of the vehicle or wait in the patrol car, to ask about the motorist’s destination and purpose, to check the validity of the driver’s license and registration, and to check the driver’s criminal history for outstanding warrants. Asking an off-topic question, such as whether a driver is carrying illegal drugs, during an otherwise lawful traffic stop does not violate the Fourth Amendment." United States v Long, 532 F3d 791, 795 (8th Cir 2008).

If the officer exceeds the permissible scope of the initial stop, the encounter becomes a de facto arrest, and any evidence obtained after that point is considered illegally obtained unless otherwise supported by probable cause. United States v Sharpe, 470 US 675, 684 (1985).

Expanding the Scope. If, however, during the course of an otherwise valid traffic stop, the officer learns additional information that gives him or her a reasonable suspicion to believe a crime has been or is being committed, the officer can expand the scope of the stop to explore the new circumstances. People v Williams, 472 Mich 308, 315, 696 NW2d 636, 641(2005) ("when a traffic stop reveals a new set of circumstances, an officer is justified in extending the detention long enough to resolve the suspicion raised").

The Motor Vehicle Exception. Generally, if the police have probable cause to search a vehicle, there is no need for them to obtain a warrant before searching it. Carroll v United States, 267 US 132, 153 (1925) (where police have probable cause, "contraband goods concealed and illegally transported in an automobile or other vehicle may be searched for without a warrant").

Practically this occurs in two situations, the police see or smell something. For example, according the the plain view doctrine, if during a valid traffic stop an officer sees drugs in plain view in the vehicle, the officer can enter the car and seize the drugs without a warrant, and then search the rest of the vehicle as they now have probable cause.

Michigan law, for example, recognizes that "the smell of marijuana alone by a person qualified to know the odor may establish probable cause to search a motor vehicle, pursuant to the motor vehicle exception to the warrant requirement." People v Kazmierczak, 461 Mich 411, 426, 605 NW2d 667 (2000). This includes the smell of "burned, burning, and unburned marijuana."Id. at 426 n13. Thus, a police officer that smells what he or she believes to be the odor of marijuana will be justified in searching the entire vehicle. This rule is obviously easy for a police officer to abuse, so it is very important to have an experienced criminal defense lawyer to challenge an officer’s observations. The law is unclear as to whether or not an officer smelling burnt marijuana is sufficient justification to search a trunk, especially if no marijuana was discovered in the passenger compartment.

Search Incident to Arrest. In New York v Belton, 453 US 454 (1981), the United States Supreme Court held that an officer can search the passenger compartment of a vehicle incident to the arrest of the driver or passenger, including the trunk and other closed compartments, even in the absence of probable cause or a warrant. In Arizona v Gant, 556 US 332, 129 S Ct 1710 (2009), the U.S. Supreme Court put an end to this overbroad application of the Belton rule, holding that no such overly broad search is permissible if the arrestee is under the control of the police and there is no reasonable possibility that he or she could actually access the vehicle.

Consent. An owner or person in control of a vehicle (i.e., presumably the driver) can give consent for a police search. In this case, no warrant is required and no probable cause is necessary. The consent must come from someone authorized to give consent, be freely given and the search must be limited to the scope of the consent.

While the police do not have to inform you that you have the right to refuse consent, "knowledge of the right to refuse is but one factor to consider in determining whether consent was voluntary under the totality of the circumstances." People v Borchard-Ruhland, 460 Mich 278, 294, 597 NW2d 1 (1999) (citing Schneckloth v Bustamonte, 412 US 218, 248–249 (1973)).

The test for determining the scope of a consent to search "is that of ‘objective reasonableness’—what would the typical reasonable person have understood by the exchange between the officer and the suspect?" Florida v Jimeno, 500 US 248 (1991).

Inventory Search/Inevitable Discovery. Even after establishing the search of a vehicle was unconstitutional because it exceeded the scope of a permissible search incident to arrest under Arizona v Gant, 556 US 332 (2009), the prosecutor will fall back on inventory search and the doctrine of "inevitable discovery". Meaning the police would have found the evidence when they impounded the vehicle and conducted an "inventory search".

The doctrine of inevitable discovery provides that evidence obtained through an unconstitutional search may "still be admitted at trial if the prosecution establishe[s] by a preponderance of the evidence that the information ultimately or inevitably would have been discovered by lawful means." People v Brzezinski, 243 Mich App 431, 435, 622 NW2d 528 (2000). The police can legally conduct an inventory search of a vehicle, without a warrant, once it has been impounded.

However, is not enough to say that just because the police had the right to conduct an inventory search, that it would have actually happened. "[T]he validity of the inventory search depends on whether there were standardized criteria, policies, or routines regulating how inventory searches were to be conducted. … The goal is to prevent inventory searches from being used as ‘a ruse for general rummaging in order to discover incriminating evidence’ and, therefore, the applicable policy ‘should be designed to produce an inventory.’ " People v Poole, 199 Mich App 261, 265, 501 NW2d 265 (1993) (quoting Florida v Wells, 495 US 1, 4 (1990)).

Exigent Circumstances/Safety. "[W]arrants are generally required to search a person’s home or his person unless the exigencies of the situation make the needs of law enforcement so compelling that the warrantless search is objectively reasonable under the Fourth Amendment." United States v Santana, 427 US 38, 42, 43 (1976).

In the context of an automobile search, Terry v Ohio, 392 US 1; 88 S Ct 1868 (1968), allows for protective search for weapons in an automobile if the officer points to "specific and articulable facts" which, along with rational inferences, alert the police that a suspect is dangerous and may gain immediate control of weapons, thereby reasonably warranting the intrusion. Michigan v Long, 463 US 1032, 1049 (1983). Hence, if the police reasonably believe the defendant to be dangerous and the automobile to contain weapons, then they may search for weapons. If the police are reasonably searching for weapons and they find other contraband, then the items found would be the subject of a valid search.

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