## Facts

- Federal narcotics agents arrested Hom Way after surveillance and found heroin; Way said he bought an ounce from “Blackie Toy,” described only as a laundry proprietor on Leavenworth Street.
- Agents went to Oye’s Laundry, operated by James Wah Toy; the record did not establish that Toy was “Blackie Toy.”
- After an agent displayed a badge and identified himself, Toy ran toward the rear living quarters; agents forcibly entered, pursued him into a bedroom, and arrested him without a warrant; no narcotics were found.
- In the bedroom, Toy denied selling narcotics but, in response to questioning, identified “Johnny” and gave his location.
- Agents went to Johnny Yee’s residence; Yee surrendered heroin and stated Toy and “Sea Dog” (Wong Sun) had brought the heroin to him.
- Agents arrested Wong Sun at his home without a warrant; no narcotics were found.
- Toy, Yee, and Wong Sun were arraigned and released on their own recognizance.
- Several days later, Toy and Wong Sun returned to the Bureau of Narcotics for questioning and gave statements in English; neither signed his statement, though Wong Sun acknowledged accuracy.
- After a bench trial, Toy and Wong Sun were acquitted of conspiracy but convicted of a substantive heroin transportation/concealment offense under 21 U.S.C. § 174; the court of appeals affirmed despite concluding both arrests lacked probable cause.

## Issues

1. Whether the warrantless arrests of Toy and Wong Sun were supported by probable cause.
2. Whether Toy’s bedroom statements were suppressible fruits of an unlawful entry and arrest.
3. Whether the heroin surrendered by Yee was suppressible as derivative evidence obtained by exploiting Toy’s unlawfully obtained statements.
4. Whether Wong Sun’s later stationhouse statement was suppressible as a fruit of his unlawful arrest, or admissible due to attenuation.
5. Whether, after excluding unlawfully obtained evidence, the remaining proof was sufficient to sustain Toy’s conviction.

## Decision

- The Supreme Court reversed and remanded.
- Toy’s arrest was not supported by probable cause; the tip was vague and from an untested source, and Toy’s flight did not supply probable cause after the agents’ unlawful intrusion.
- Toy’s bedroom statements were obtained as an immediate product of the unlawful entry and arrest and were inadmissible against Toy.
- The heroin obtained from Yee was also inadmissible against Toy because it was acquired by exploiting Toy’s unlawfully obtained statements.
- Wong Sun’s later statement at the narcotics office was admissible because intervening events (arraignment, release, passage of days, and his voluntary return) sufficiently attenuated the connection to the unlawful arrest.
- With the suppressed evidence removed, the remaining proof was insufficient to sustain Toy’s conviction; Toy’s conviction was reversed.

## Legal Principles

- Probable cause for arrest cannot rest on vague, uncorroborated information from an untested source, particularly where the suspect is not reliably identified.
- Flight in response to police presence does not cure a prior unlawful entry or retroactively create probable cause for an arrest.
- The exclusionary rule applies to both tangible evidence and verbal statements when they derive directly from unlawful police conduct.
- Derivative evidence obtained by exploiting unlawfully obtained statements may be suppressed as fruit of the initial illegality.
- A confession may be admissible despite an unlawful arrest when intervening circumstances and voluntary conduct render the causal connection sufficiently attenuated to dissipate the taint.
- Suppression is generally limited to violations of the defendant’s own Fourth Amendment interests, requiring defendant-specific admissibility analysis for shared evidence.

## Conclusion

The Court held that Toy’s arrest lacked probable cause and that both his immediate post-arrest statements and the heroin obtained through those statements were suppressible fruits as to Toy, requiring reversal of his conviction; by contrast, Wong Sun’s later voluntary statement was admissible because intervening events attenuated any taint from his unlawful arrest.


Wong Sun v. United States, 371 U.S. 471 (1963)