D participated in a narcotics distribution scheme in Anchorage, Alaska, with his girlfriend, her family, and other associates. D was allegedly the supplier of drugs, which he arranged to be smuggled from California. D was charged with conspiracy to distribute cocaine in violation of 21 U.S.C. § 846. He moved to dismiss the indictment because it did not allege the commission of an overt act in furtherance of the conspiracy. The motion was denied and D was convicted. The Ninth Circuit reversed. It held that P must prove at trial that D has committed an overt act in furtherance of a narcotics conspiracy, but the act need not be alleged in the indictment because ''courts do not require as detailed a statement of an offense's elements under a conspiracy count as under a substantive count.'' The Supreme Court granted certiorari.