The Supreme Court ruled that, in a federal criminal case, the defendant must have prior knowledge that their partner would carry a firearm and actively participate in the crime to be charged with violating a federal criminal statute. The case in question involved a drug transaction. The defendant was charged for using or carrying a firearm during a violent crime or drug trafficking. The Supreme Court stated that the trial court's jury instructions were insufficient, as they did not mandate proof that the defendant knew in advance that their accomplice had a firearm.

For the aiding and abetting of a § 924(c) offense, a defendant can be convicted even if they only aided or participated in some of the crime-related stages. However, the defendant must have the intent to facilitate the entire crime charged, including any predicate crime and gun use, and must actively participate in the criminal venture while having full knowledge of the circumstances constituting the charged offense.

If an accomplice in a drug transaction is aware that their co-conspirator will carry a gun, they are considered an aider and abettor of a § 924(c) violation. To be regarded as such, the defendant must have the opportunity to alter the plan or withdraw from the enterprise, and they must possess prior knowledge of the firearm. The defendant's intent to aid and abet a § 924(c) violation is determined by their decision to participate in the illegal scheme with full knowledge.

The District Court's jury instructions were inadequate in a § 924(c) prosecution as they failed to explain that the defendant needed prior knowledge of a firearm's presence. The Supreme Court returned the case to the Tenth Circuit to determine the impact of the District Court's errors.

The Court's new approach to mens rea for aiding and abetting is unprecedented and places a difficult burden on the prosecution. The Court's analysis is incorrect because it confuses intent and motive. In cases involving aiding and abetting of § 924(c) offenses, the prosecution must prove intent, which is difficult because only the defendant knows it. The dissenting opinion disagrees with the Court's decision to place the burden of proof on the government to prove that an alleged aider and abettor of a § 924(c) offense had a realistic opportunity to refrain from engaging in the conduct at issue, arguing that it goes against common-law tradition and case law.