In United States v. Wilson, 895 F.2d 168 (4th Cir. 1990), a DEA agent posted at a Virginia airport observed the defendant deplaning from New York, and noticed that he was looking about nervously.
The agent followed the defendant, identified himself, and engaged him in conversation about the DEA's effort to stop the flow of illegal drugs into the area from New York.
When the agent asked the defendant if he could search his bag, the defendant replied, "Go ahead." The agent then asked the defendant whether he could search his person. The defendant said nothing, but shrugged his shoulders and extended his hands in the air.
The agent performed the pat-down search and detected a very hard substance in the defendant's groin area. The defendant was taken into custody and a body search revealed, inter alia, 131.5 grams of cocaine.
The Fourth Circuit held that, under the totality of the circumstances, the defendant's act of responding to a request for permission to conduct a pat-down search by raising his arms in the air constituted an implied consent. 895 F.2d at 171.