The following excerpt is from USA v. Stephens, 206 F.3d 914 (9th Cir. 2000):
This merely illustrates the effectiveness of the technique employed by law enforcement officials. An innocent person may be inconvenienced but a guilty person frequently will give himself away. The inconvenience of the innocent does not turn the encounter into an unlawful seizure. An innocent person under these circumstances would not feel threatened by a simple question regarding ownership of a bag. As Florida v. Bostick makes clear, it is only when the "innocent" feel compelled to cooperate that the encounter runs afoul of the Fourth Amendment. Stephens put himself in a vulnerable position when he undertook to transport by bus such a large quantity of drugs. It was the drugs that he undertook to transport, not the conduct of the police, that led him to deny his ownership of the bag.
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