Justice Thomas delivered the opinion of the Court.
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The question in this case is how the mental state requirement under the [Controlled Substances Act] for knowingly manufacturing, distributing, or possessing with intent to distribute “a controlled substance” applies when the controlled substance is in fact an analogue. The answer begins with §841(a)(1), which expressly requires the Government to prove that a defendant knew he was dealing with “a controlled substance.” The Analogue Act does not alter that provision, but rather instructs courts to treat controlled substance analogues “as . . . controlled substance[s] in schedule I.” §813. Applying this statutory command, it follows that the Government must prove that a defendant knew that the substance with which he was dealing was “a controlled substance,” even in prosecutions involving an analogue. [Footnote omitted.]
That knowledge requirement can be established in two ways. First, it can be established by evidence that a defendant knew that the substance with which he was dealing is some controlled substance—that is, one actually listed on the federal drug schedules or treated as such by operation of the Analogue Act—regardless of whether he knew the particular identity of the substance. Second, it can be established by evidence that the defendant knew the specific analogue he was dealing with, even if he did not know its legal status as an analogue. The Analogue Act defines a controlled substance analogue by its features, as a substance “the chemical structure of which is substantially similar to the chemical structure of a controlled substance in schedule I or II”; “which has a stimulant, depressant, or hallucinogenic effect on the central nervous system that is substantially similar to or greater than” the effect of a controlled substance in schedule I or II; or which is represented or intended to have that effect with respect to a particular person. §802(32)(A). A defendant who possesses a substance with knowledge of those features knows all of the facts that make his conduct illegal, just as a defendant who knows he possesses heroin knows all of the facts that make his conduct illegal. A defendant need not know of the existence of the Analogue Act to know that he was dealing with “a controlled substance.”
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III
The District Court’s instructions to the jury did not fully convey the mental state required by the Analogue Act. The jury was instructed only that McFadden had to “knowingly and intentionally distribut[e] a mixture or substance that has an actual, intended, or claimed stimulant, depressant, or hallucinogenic effect on the central nervous system” substantially similar to that of a controlled substance. App. 40.
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For the foregoing reasons, we vacate the judgment of the Court of Appeals and remand the case for further proceedings consistent with this opinion.
It is so ordered.
SCALIA, KENNEDY, GINSBURG, BREYER, ALITO, SOTOMAYOR, and KAGAN, JJ., joined. ROBERTS, C. J., filed an opinion concurring in part and concurring in the judgment.
CHIEF JUSTICE ROBERTS, concurring in part and concurring in the judgment.
I join the Court’s opinion, except to the extent that it says the Government can satisfy the mental state requirement of Section 841(a)(1) “by showing that the defendant knew the identity of the substance he possessed.” Ante, at 5. Section 841(a)(1) … suggests that a defendant needs to know more than the identity of the substance; he needs to know that the substance is controlled.[Citations omitted.]
….The Court says that knowledge of the substance’s identity suffices because “ignorance of the law is typically no defense to criminal prosecution.” Ante, at 5. I agree that is “typically” true. But when “there is a legal element in the definition of the offense,” a person’s lack of knowledge regarding that legal element can be a defense. Liparota v. United States, 471 U. S. 419, 425, n. 9 (1985). And here, there is arguably a legal element in Section 841(a)(1)— that the substance be “controlled.”
The analogy the Court drew in Liparota [v. United States, 471 U. S. 419 (1985)] was to a charge of receipt of stolen property: It is no defense that the defendant did not know such receipt was illegal, but it is a defense that he did not know the property was stolen. Here, the argument goes, it is no defense that a defendant did not know it was illegal to possess a controlled substance, but it is a defense that he did not know the substance was controlled.
Ultimately, the Court’s statements on this issue … should … not be regarded as controlling if the issue arises in a future case.