In the case of Sherman v. United States in 1957, the Supreme Court ruled that entrapment had occurred when a government informant induced Robert Weil Sherman to sell narcotics. The court held that if the criminal conduct was "the product of the creative activity" of law enforcement officials, it constituted entrapment and thus could not be prosecuted. In this case, an undercover agent befriended Sherman who was recovering from drug addiction and repeatedly asked him for drugs over several weeks until he finally relented and sold them to him. The court found that since there was no evidence suggesting that Sherman would have committed this crime without being coerced by law enforcement, his conviction should be overturned due to entrapment.

In the dissenting opinion for Sherman v. United States, Justice Frankfurter argued that the majority's decision to overturn Sherman's conviction on grounds of entrapment was misguided. He contended that while government agents may have provided opportunities for Sherman to commit a crime, they did not induce him into criminal conduct he was otherwise unwilling to engage in. The justice emphasized that it is crucial to distinguish between trapping innocent people into crimes and catching criminals in the act. In this case, he believed it fell under the latter category as there were clear indications of predisposition towards narcotics trafficking on part of Sherman before any interaction with government agents took place. Therefore, according to Justice Frankfurter’s view, no entrapment occurred and thus his conviction should stand.