Section 201 of title 18 prohibits bribing or giving gratuities to public officials or sworn witnesses. Bribery is the greater offense because it involves corrupt intent. To be guilty of corrupt intent, a party must intend to influence an official act or intend to influence a public official to commit or allow any fraud against the United States, or intend to induce a public official to act in violation of his lawful duty. However, the intent required for prosecution for payment or receipt of a simple gratuity involves merely payments or gifts made to an officials or witnesses because of their authority or position. The prosecutor need not relate the payment to any specific identifiable official acts performed. Therefore, evidence resulting in bribery acquittals can be sufficient for gratuity convictions. The crime of either bribery or gratuity is complete when the donor offers to pay the witness or official; acceptance of illegal payment is established when the witness or official solicits, takes, or agrees to take payment. A bribery conviction is not contingent on showing that the public official fulfilled a promise, because the essence of the crime is accepting the bribe. Acts illegally influenced by bribes include any official acts for which the official is responsible. Bribes and gratuities may be anything of material value. Although challenges to bribery or gratuity charges based on allegations of unconstitutional vagueness do not fare well in court, some defenses are more successful. These include entrapment challenges, in which it must be shown that the crime was government-induced, and the impossibility defense, showing that the act was committed before the bribe was offered. Footnotes are included.