On March 5, the U.S. Supreme Court issued an opinion explicating the elements of a federal aiding and abetting charge, providing the most thorough discussion of the subject in its history. Destined for the criminal law case books, the opinion also will guide trial lawyers and judges in approaching the common charge of aiding and abetting, at least in federal cases.Rosemond v. United States, 2014 DJDAR 2674, reversed the 10th U.S. Circuit Court of Appeals and rejected jury instructions that court had approved in a prosecution for aiding and abetting a federal offense, under the general federal aiding and abetting statute, 18 U.S.C. Section 2. A defendant can be charged under Section 2 with aiding any federal crime; he is not alleged to have committed the principal offense himself, but rather to have helped the offense occur. The prosecution must prove two elements in any aiding and abetting case: (1) the act that the defendant took to aid the offense, and (2) the intent that the defendant had to make the offense happen. For trial lawyers, Rosemond contributed something new to each element. Justus Rosemond was tried for aiding and abetting a violation of 18 U.S.C. Section 924(c), the often-prosecuted federal offense of using or carrying a firearm in connection with a drug trafficking crime or another violent crime. That charge carries substantial mandatory consecutive penalties, which, in Rosemond's case, meant an additional 10 years in prison. Section 924(c) poses a particularly difficult legal question for aiding and abetting law. That crime is, in a term that Justice Elena Kagan coined in her 7-2 opinion for the court, a "combination offense." Every Section 924(c) offense includes both an independent crime, such as drug trafficking, and the employment of a firearm during that crime. For this reason, Rosemond presented the possibility of convicting a defendant who merely expected to facilitate a simple drug transaction, but who ended up with a dramatically increased penalty when another participant brought a gun. Rosemond conceded that he was one of a trio of sellers at what Kagan called "a drug deal gone bad." When a buyer tried to abscond with the contraband, a seller pulled out a semiautomatic handgun and fired shots. Rosemond claimed he was not the gunman and first learned of the firearm when it was fired. At Rosemond's trial, as to the "act" element, the court required that the jury find that Rosemond acted to aid the drug transaction - not necessarily the firearm use. Rosemond argued futilely that the jury must also find that he acted to aid the firearm use, as the majority of circuits required. In an undisputed instruction on the "intent" element, the judge instructed the jury that it must find that Rosemond knew that his cohort used a firearm, with no requirement as to when Rosemond obtained that knowledge. Kagan's majority opinion closely examined both elements. As to the "act" element, relying on treatises from the 19th and early 20th century, she concluded that Section 2 incorporated the common law's imposition of aiding and abetting liability on a person (possessing the required intent) who acts to facilitate any element of a criminal venture. This meant that the instruction given Rosemond's jury as to the act was correct: To convict him of aiding Section 924(c), the jury need find only that he acted to advance the drug transaction, which he indisputably did here as one of the trio of sellers. He need not have also acted to further the gun use. Rosemond's approach to the act needed to aid a Section 924(c) offense differs from that in the 9th Circuit and seven other circuits, which previously required proof that a defendant acted to aid the firearm use. For example, the 9th Circuit has reversed a conviction of a defendant who helped plan and then participate in a jewelry store robbery calling for the robbers to brandish firearms, but who "took no action at the scene of the crime" to facilitate her cohort's brandishing of a firearm. United States v. Nelson, 137 F.3d 1094, 1103-04 (9th Cir. 1988). Further, the approach to the "act" in Rosemond may prompt fresh thought about the proof required in other aiding and abetting cases. In the 9th Circuit, Model Criminal Jury Instruction 5.1 requires that an aiding and abetting defendant act to facilitate all the elements of the principal offense, requiring proof that "the defendant knowingly and intentionally aided ... each element." Applying the "each element" requirement, the circuit has, for instance, reversed the armed bank robbery conviction of a getaway driver where there was no proof the driver had assisted the use of the guns during the robbery. United States v. Dinkane, 17 F.3d 1192, 1197 (9th Cir. 1994). Rosemond's construction of the "intent" element, in contrast, may provide assistance to some defendants. Because the common law requires that an aider and abettor intend the full scope of an offense, the defendant must intend both the drug crime and the gun use to be guilty of facilitating Section 924(c). Thus, Rosemond held that "[a]n active participant in a drug transaction has the intent needed to aid and abet a Section 924(c) violation when he knows that one of his confederates will carry a gun." That much is consistent with the jury instructions given Rosemond's jury and that typically have been provided in federal cases. More significantly, though, Rosemond held that the knowledge must be "advance knowledge" that enables the defendant "to make the relevant legal (and, indeed, moral) choice" to participate in the charged crime. That is, Rosemond held that it must be "knowledge at a time the accomplice can do something with it - most notably, opt to walk away." In articulating this requirement, the court rejected the government's position that the intent element is satisfied when a defendant learns of the firearm during the offense, even late in the transaction. The court reasoned that a drug seller does not make the legal choice to knowingly participate in an offense involving a firearm "when that knowledge comes too late for him to reasonably act upon it." In other words, proof that the defendant learned of the gun when it was too dangerous to withdraw from the crime does not suffice. From the Rosemond dissent and the majority's response to it, one can see how the construction of the intent requirement may raise new issues in some trials. Dissenting Justice Samuel Alito argued that the majority had created a "strange and difficult burden for the prosecution" by conflating the defendant's traditional burden to prove an affirmative defense of duress with the prosecution's burden to prove the elements of the crime. That is, Alito believed that, once the government proves that the defendant knew of the firearm at any point, it had satisfied its burden, and it should be up to the defendant to demonstrate that he could not have walked away without exposing himself or others to harm greater than he would cause by continuing with the crime. Kagan's footnoted response suggested that the prosecution often will rely on inferences from all the facts and circumstances of the case to prove advance knowledge. In aiding and abetting cases after Rosemond, then, the prosecution can be held to the burden of demonstrating beyond a reasonable doubt that the defendant had sufficient advance knowledge of the complete crime to walk away safely. Might a getaway driver assert that he did not learn until too late that his cohorts had robbed a bank, rather than some other store? Could a defendant who housed smuggled illegal aliens claim that he did not know their status until it was too dangerous for him to walk away from the smuggling organization? There likely will be some cases where defendants seek to have the government prove sufficient foreknowledge to a jury. The court remanded Justus Rosemond's case to the 10th Circuit because the instruction in his case failed to require foreknowledge. Rosemond may or may not prevail on remand; it will be up to the 10th Circuit to determine whether the unobjected-to instruction was plainly erroneous and whether the error was harmless. Regardless, Rosemond's case will become the leading authority interpreting the basics of the federal aiding and abetting statute that has been on the books for decades.