> For the complete documentation index, see [llms.txt](https://studies-de-jure.gitbook.io/learn/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://studies-de-jure.gitbook.io/learn/sourcebooks/introduction-to-law/introductory-criminal-procedure-principles/carroll-v.-united-states/brief-carroll-v.-united-states.md).

# Brief: Carroll v. United States

**Facts**

* Two undercover prohibition agents, acting in plain clothes, were patrolling the highway between Grand Rapids and Detroit, Michigan.
* They recognized George Carroll and John Kiro, individuals they knew to be involved in bootlegging activities. The agents had previously attempted to purchase illegal liquor from Carroll and Kiro, but the transaction was never completed.
* Several months later, the agents encountered the Carrolls driving an automobile on the same stretch of road. The agents stopped the vehicle, searched it without a warrant, and discovered 68 bottles of illegal liquor concealed behind the upholstery.
* The Carrolls were arrested and subsequently convicted of violating the National Prohibition Act. At trial, the seized liquor was admitted into evidence.

**Issue:** Did the warrantless search and seizure of the automobile and its contents violate the Fourth Amendment's protection against unreasonable searches and seizures?

* **Specifically, did the Fourth Amendment require a warrant for the search of a moving vehicle when the officers had probable cause to believe it contained contraband?**

**Holding:** No. The search and seizure were valid. The warrantless search of an automobile, based on probable cause to believe it contains contraband, does not violate the Fourth Amendment.

**Rule:** The Fourth Amendment protects against unreasonable searches and seizures. However, this protection is **not absolute**. **The requirement for a warrant is subject to certain exceptions**. One such **exception is the "automobile exception."**

* allows for the warrantless search of a motor vehicle **if there is probable cause to believe that the vehicle contains contraband or evidence of a crime**.
* REMINDER: **Probable cause exists when**
  * **The facts and circumstances within the officers' knowledge, and of which they have reasonably trustworthy information, are sufficient in themselves to warrant a man of reasonable caution in the belief that an offense has been or is being committed.**

**Analysis**

* The rationale behind this exception is the **inherent mobility of vehicles, which creates a risk that the evidence could be moved or destroyed before a warrant could be obtained**.
* Distinction between the search of a dwelling and the search of a vehicle.
  * since the beginning of the government, there has been a recognized difference between **searching a dwelling, where a warrant could readily be obtained**, DIFF FROM **searching a conveyance like a ship or automobile for contraband, where the mobility of the conveyance made obtaining a warrant impractical**.
  * obtaining a warrant to search a vehicle suspected of carrying contraband was **often impractical**.
  * a vehicle could quickly be moved outside the jurisdiction of the officers, potentially thwarting law enforcement efforts.
  * Conclusion:
    * **probable cause** to search the vehicle **based on the information they possessed regarding the Carroll brothers’ bootlegging activities and their prior interactions with them**.
      * They had encountered the Carrolls on a known bootlegging route
      * they had prior knowledge of their involvement in the illegal liquor trade.
      * This knowledge, **combined with the observation of the Carrolls driving on that particular road**, provided sufficient probable cause to believe that the vehicle contained illegal liquor.


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