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Illinois v. Gates

Supreme Court of the United States · 1983 · Criminal Procedure

Criminal ProcedureFourth Amendmentprobable causetotality of circumstancesinformant tipsprobable causesearch warrantanonymous tip

Facts

Bloomingdale police received an anonymous letter stating that Lance and Susan Gates were selling drugs, that Susan would drive their car to Florida to be loaded with drugs, and that Lance would fly down and drive it back, and that drugs were also in their basement. Detective Mader confirmed that Lance Gates lived in Bloomingdale, learned that "L. Gates" had a reservation to fly to West Palm Beach, and DEA surveillance confirmed that he flew there, went to a hotel room registered to Susan Gates, and left the next morning driving north in a car bearing Illinois plates issued to him. Mader submitted an affidavit recounting these facts and the letter, and a state judge issued a warrant for the Gateses' residence and automobile. When the Gateses returned home, police searched the car and home and found marihuana and other contraband.

Issue

Whether a magistrate may find probable cause to issue a search warrant based on an anonymous informant's tip that does not independently satisfy the Aguilar-Spinelli two-pronged test, but is substantially corroborated by police investigation. More broadly, whether probable cause in this context should be assessed under rigid separate prongs or under a totality-of-the-circumstances approach.

Rule

Probable cause is determined under a totality-of-the-circumstances analysis. The issuing magistrate must make a practical, commonsense decision whether, given all the circumstances set forth in the affidavit, including the veracity and basis of knowledge of persons supplying hearsay information, there is a fair probability that contraband or evidence of a crime will be found in a particular place; a reviewing court asks only whether the magistrate had a substantial basis for concluding that probable cause existed.

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

Police in Columbus, Ohio, receive an anonymous email stating that Nina Patel is using her townhouse to distribute pills, that her brother Arjun will fly to Phoenix on Thursday night, meet Nina there, and the two will drive back to Ohio in Nina’s silver SUV by Saturday morning with drugs hidden in a rear panel. Detectives verify that Arjun boarded the flight, that Nina was waiting at a motel near the airport, and that the pair began driving east in the silver SUV the next morning. A magistrate issues a warrant to search the SUV.

If Nina moves to suppress the pills found in the SUV, what is the strongest argument that the warrant was supported by probable cause?

Explanation. Probable cause is evaluated under a totality-of-the-circumstances approach. Veracity, reliability, and basis of knowledge remain relevant, but they are not rigid, independent prerequisites. Here, police corroborated significant predicted future conduct, which supports the inference that the informant had access to reliable inside information. That gave the magistrate a substantial basis to find a fair probability that drugs would be found in the SUV.