Skip to main content

Carroll v. United States 1925

Carroll v. United States 1925

Appellants: George Carroll and John Kiro

Appellee: United States

Appellants' Claim: That searching their car for illegal liquor without a search warrant violated the Fourth Amendment.

Chief Lawyer for Appellants: Thomas E. Atkinson and Clare J. Hall

Chief Lawyers for Appellee: John G. Sargent, Attorney General, and James M. Beck, Solicitor General

Justices for the Court: Louis D. Brandeis, Pierce Butler, Joseph McKenna, Edward Terry Sanford, William Howard Taft, Willis Van Devanter

Justices Dissenting: James Clark McReynolds, George Sutherland

Date of Decision: March 2, 1925

Decision: The Supreme Court affirmed appellants' convictions.

Significance: In Carroll, the Supreme Court decided that law enforcement officers do not need to get a warrant to search an automobile or other movable vehicle. Law enforcement only needs probable cause to believe the automobile has evidence of a crime.

The Fourth Amendment of the U.S. Constitution protects privacy. It requires law enforcement officers to get a warrant to search a house or other private place for evidence of a crime. To get a warrant, officers must have probable cause, which means good reason to believe the place to be searched has evidence of a crime. In Carroll v. United States, the Supreme Court had to decide whether officers need a warrant to search an automobile.


In January 1919 the United States adopted the Eighteenth Amendment to the U.S. Constitution. The Eighteenth Amendment made it illegal to manufacture, sell, and transport alcohol in the United States. Because many Americans still wanted to drink alcohol, gangs of organized criminals entered the liquor trade. They made their own alcohol for sale in the United States and smuggled alcohol in from other countries.

Under the Volstead Act, Congress gave federal law enforcement the power to seize vehicles and arrest persons illegally transporting alcohol. Fred Cronenwett was a federal law enforcement officer. On September 29, 1921, Cronenwett went undercover to an apartment in Grand Rapids, Michigan. There he met John Carroll, who took Cronenwett's order for three cases of whiskey. Although Carroll never delivered the whiskey, Cronenwett remembered what Carroll and his car looked like.

A few months later on December 15, Cronenwett and two other officers were driving down the highway from Grand Rapids to Detroit, Michigan, when they passed Carroll and John Kiro going the other way. Smugglers frequently used that road to bring alcohol into the country from Canada. The officers turned around, caught up to Carroll and Kiro, and told them to pull over. The officers then searched the car without a warrant and found 69 quarts of whiskey. The United States convicted Carroll and Kiro of violating the Volstead Act and the Eighteenth Amendment.

The Automobile Exception

Carroll and Kiro appealed their convictions to the U.S. Supreme Court. They said searching their car without a warrant violated the Fourth Amendment. With a 7-2 decision, the Supreme Court disagreed and affirmed their convictions.

Chief Justice William Howard Taft wrote the opinion for the Court. Taft said the Fourth Amendment protects privacy by requiring searches to be reasonable. It does not, however, require a warrant for all searches. When police believe a private home has evidence of a crime, it is reasonable to require them to get a warrant before searching the place. The house cannot go anywhere.

The case is different with automobiles and other moving vehicles. When a police officer sees an automobile that might contain evidence of a crime, there is no time to get a search warrant. The driver can hide the car or leave the state and escape the police officer's jurisdiction, or area of power. That means it is unreasonable to require the police to get a warrant to search an automobile.

Taft emphasized, however, that officers enforcing the Volstead Act could not stop and search cars at random. To conduct any search, the Fourth Amendment requires probable cause, which means good reason to believe the place to be searched has evidence of a crime. That meant officers enforcing the Volstead Act were limited to searching cars that probably contained illegal alcohol.

The Supreme Court decided that Cronenwett and his fellow officers had probable cause to search Carroll and Kiro's car. Cronenwett knew Carroll was involved in the liquor trade because Cronenwett went undercover to order illegal whiskey from Carroll. Cronenwett also knew that alcohol smugglers often used the road between Detroit and Grand Rapids. Chief Justice Taft said that when Cronenwett saw Carroll driving on that road, Cronenwett had good reason to believe the car contained illegal alcohol, which it did.

Uncommon Law

Two justices dissented, meaning they disagreed with the Court's decision. Justice James Clark McReynolds wrote a dissenting opinion. McReynolds disagreed that the Fourth Amendment allows law enforcement to search a car without a warrant.


T he United States adopted the Eighteenth Amendment to the U.S. Constitution in January 1919. The Eighteenth Amendment made it illegal to manufacture, sell, and transport alcohol, including liquor, beer, and wine, in the United States. This was the beginning of the period of time known as Prohibition.

Prohibition happened for many reasons. Some religious groups, especially Protestants, believed alcohol was immoral. Medical reports suggested that alcohol caused health problems and early death. Politicians in favor of prohibition said it would reduce crime. Prejudice against foreigners who used alcohol also fueled the movement for Prohibition. This was especially true of prejudice toward Germans, against whom the United States fought in World War I from 1917 to 1918.

Prohibition, however, did not work very well. Crime increased as organized criminals supplied illegal alcohol to those who wanted it. Poor people who could not afford good alcohol often were poisoned by bad alcohol. Closing saloons eliminated a popular meeting place for working class Americans. When the Great Depression hit the United States in the 1930s, Americans decided legalizing alcohol would help the economy. The United States ended prohibition with the Twenty-First Amendment to the Constitution in 1932.

Under English common law at the time the United States adopted the Fourth Amendment, police could arrest and search a man without a warrant only if he was wanted for a felony or had committed a misdemeanor in front of the officer. (Felonies are serious crimes such as murder, while misdemeanors are less serious crimes such as reckless driving.) Because violating the Volstead Act was a misdemeanor, McReynolds thought Cronenwett needed a warrant to arrest Carroll and Kiro and search their car.

McReynolds also did not think Cronenwett had probable cause to search the car. McReynolds asked, "Has it come about that merely because a man once agreed to deliver whiskey, but did not, he may be arrested whenever thereafter he ventures to drive an automobile on the road to Detroit!"

Despite McReynolds's concerns, Carroll has remained good law. Federal and state law enforcement officers with probable cause to believe a car has evidence of a crime may stop and search it without a warrant.

Suggestions for further reading

Baughman, Judith S., ed. American Decades: 1920-1929. Detroit: Gale Research, 1996.

Franklin, Paula A. The Fourth Amendment. Englewood Cliffs: Silver Burdett Press, 1991.

Persico, Deborah A. Mapp v. Ohio: Evidence and Search Warrants. Enslow Publishers, Inc., 1997.

—-. New Jersey v. T.L.O: Drug Searches in Schools. Enslow Publishers, Inc., 1998.

Shattuck, John H.F. Rights of Privacy. Skokie: National Textbook Co., 1977.

Vile, John R. Encyclopedia of Constitutional Amendments, Proposed Amendments, and Amending Issues. Santa Barbara: ABC-CLIO, Inc., 1996.

Wetterer, Charles M. The Fourth Amendment: Search and Seizure. Enslow Publishers, Inc., 1998.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Carroll v. United States 1925." Supreme Court Drama: Cases That Changed America. . 22 Jan. 2019 <>.

"Carroll v. United States 1925." Supreme Court Drama: Cases That Changed America. . (January 22, 2019).

"Carroll v. United States 1925." Supreme Court Drama: Cases That Changed America. . Retrieved January 22, 2019 from

Learn more about citation styles

Citation styles gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, cannot guarantee each citation it generates. Therefore, it’s best to use citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

The Chicago Manual of Style

American Psychological Association

  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.