Entrapment is an issue that must be considered in designing sting operations.
John De Lorean was arrested in 1982 for selling cocaine to undercover police; in court, De Lorean argued that the police had asked him to sell them the cocaine (and threatened him as a form of coercion); he was found "not guilty". De Lorean's attorney stated in Time (March 19, 1984), "This [was] a fictitious crime. Without the Government, there would be no crime."
The defense of entrapment was unsuccessful in the Abscam operation in which which several Congressmen were convicted of bribery.
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Alternate use: Entrapment 1999 movie starring Sean Connery and Catherine Zeta-Jones.