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Wong Sun v. United States

Supreme Court of the United States · 1963 · Criminal Procedure

Criminal ProcedureFourth Amendmentexclusionary rulefruit of the poisonous treeattenuationprobable causewarrantless arrestunlawful entry

Facts

After arresting Hom Way and finding heroin on him, federal narcotics agents relied on his statement that he had bought heroin from "Blackie Toy," proprietor of a laundry on Leavenworth Street, and went without a warrant to petitioner Toy's laundry. Agent Wong initially posed as a customer, then identified himself as a narcotics agent; Toy shut the door and ran, and the agents broke in, arrested him in his bedroom, and obtained statements that led them to Johnny Yee, who surrendered heroin. Toy then identified Wong Sun, who was later arrested without a warrant; no narcotics were found in Wong Sun's apartment. Days later, after arraignment and release on recognizance, both petitioners gave unsigned statements to a narcotics agent, and the Government used Toy's bedroom statements, Yee's heroin, and both unsigned statements at trial.

Issue

Whether evidence and statements obtained after the petitioners' warrantless arrests were admissible, or instead had to be excluded as fruits of unlawful arrests and entries. More specifically, the case asked whether Toy's statements and the heroin found through them were tainted fruits, whether Wong Sun's later unsigned statement was sufficiently attenuated from his arrest, and what evidence could be used to corroborate each petitioner's admissions.

Rule

An arrest, with or without a warrant, must rest on probable cause rather than mere suspicion, and officers may not rely on vague, untested information insufficient to support a warrant. Under the exclusionary rule, not only tangible evidence directly seized through unlawful police conduct, but also verbal evidence derived immediately from unlawful entry or arrest, must be excluded unless obtained from an independent source or by means sufficiently distinguishable to purge the primary taint. The proper inquiry is whether the challenged evidence was obtained by exploitation of the primary illegality or instead by means sufficiently distinguishable to dissipate the taint.

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One of 10 multiple-choice questions for this case. Pick an answer to see why.

In Seattle, federal narcotics agents arrest Luis Moreno with heroin. For the first time, Moreno tells them he bought it from "Red" who runs "a repair shop somewhere on Aurora Avenue." Without seeking a warrant, agents drive to a shop called Northline Auto, enter the back room, and arrest Devin Cruz, whom they have never before linked to the nickname or address.

Was the warrantless arrest of Devin most likely supported by probable cause?

Explanation. The majority opinion requires firmer ground than mere suspicion. Information from a first-time informant with no established reliability, combined with only a vague nickname and a broad location, is too imprecise and untested to support probable cause. The Court stressed that officers cannot rely on information insufficient to obtain a warrant and then use that lesser showing to justify a warrantless arrest. Probable cause does not require proof beyond a reasonable doubt, but it does require facts warranting a person of reasonable caution in believing the suspect committed a felony.