On May 3, 1978, the Bloomingdale Police Department (P) received by mail an anonymous handwritten letter. The letter detailed to the police the adventures of Sue and Lance Gates (Ds). It told the police that Ds were drug dealers. Most of their buys were done in Florida. Sue then drives their car to Florida, where she leaves it to be loaded up with drugs, then Lance flies down and drives it back. Sue flies back after she drops the car off in Florida. The letter told police that on May 3 she is driving down there again and Lance will be flying down in a few days to drive it back. At the time Lance drives the car back, he has the trunk loaded with over $100,000.00 in drugs. Presently they have over $100,000.00 worth of drugs in their basement. P decided to pursue the tip. They quickly discovered who Ds were. A confidential informant also gave them a recent address. The police also learned that 'L. Gates' had made a reservation on Eastern Airlines Flight 245 to West Palm Beach, Fla., scheduled to depart from Chicago on May 5 at 4:15 p. m. DEA was called into the case to surveil the flight and to follow Ds on their adventures. Lance met an unidentified woman and left a motel in a Mercury bearing Illinois license plates and drove northbound on an interstate highway frequently used by travelers to the Chicago area. The DEA informed P that the license plate number on the Mercury was registered to a Hornet station wagon owned by Ps. The agent also advised Mader that the driving time between West Palm Beach and Bloomingdale was approximately 22 to 24 hours. P signed an affidavit setting forth the foregoing facts and submitted it to a judge with a copy of the anonymous letter. The judge issued a search warrant for Ds' residence and their automobile. The anonymous letter predicted, the movements of the couple. When Ds returned home, P were awaiting them. They found approximately 350 pounds of marijuana in the trunk. A search of the home revealed marihuana, weapons, and other contraband. The Illinois Circuit court ordered suppression of all these items, on the ground that the affidavit failed to support the necessary determination of probable cause to believe that Ds' automobile and home contained the contraband in question. This decision was affirmed. The Illinois Supreme Court concluded that, standing alone, the anonymous letter sent to P would not provide the basis for probable cause to believe contraband would be found in Ds' car and home. First, the 'veracity' prong was not satisfied because 'there was simply no basis for concluding that the anonymous person who wrote the letter to the Bloomingdale Police Department was credible.' Only 'innocent' details are corroborated. The letter gave no indication of the basis of its writer's knowledge of Ds' activities. The letter provides virtually nothing from which one might conclude that its author is either honest or his information reliable; likewise, the letter gives absolutely no indication of the basis for the writer's predictions regarding the criminal activities. The Supreme Court granted certiorari.