When is a doctor a doctor and when is a doctor a drug dealer? In early March, the U.S. Supreme Court heard oral argument in two consolidated cases—Ruan v. United States and Kahn v. United States—to address where that line is drawn. Since the mid-1970s, doctors who prescribe controlled substances are not subject to prosecution for unlawful distribution under the Controlled Substances Act unless those prescriptions "fall outside the usual course of professional practice." United States v. Moore, 423 U.S. 122, 124 (1975). If a doctor prescribing controlled substances believes, mistakenly, that he or she is acting within the usual course of professional practice, that sounds like medical malpractice, but is it also a felony? The court granted certiorari in Ruan and Kahn to address a circuit split on whether a physician who prescribes controlled substances may be convicted of unlawful distribution under 21 U.S.C. §841(a)(1) without regard to whether, in good faith, that physician believed the prescriptions to fall within an acceptable course of professional practice.

The issue at stake in Ruan and Kahn seems primed to fit a pattern of recent cases where the Supreme Court has addressed interpretations of criminal statutes that threaten to sweep too far. In cases like Bond v. United States, 572 U.S. 844 (2014), Yates v. United States, 574 U.S. 528 (2015), and most recently in Van Buren v. United States, 141 S. Ct. 1648 (2021), the Supreme Court narrowly has interpreted broadly written criminal statutes based on a close—sometimes strained—analysis of statutory language. In these cases, the court, at times, has acknowledged the larger problem of overcriminalization via statutes susceptible of sweeping in innocent or de minimis conduct, but nevertheless anchors its decisions in the text—without express reliance on broader judicial doctrines. The parties' arguments and the justices' comments during oral argument in Ruan and Kahn, however, hint at the possibility that the court may break its recent pattern and delineate the boundary between medical malpractice and felony drug dealing on a more far-reaching doctrinal foundation—the bedrock criminal law principle that each statutory element distinguishing lawful from unlawful conduct must be done with mens rea.

Statutory Framework and the Good Faith Defense

The Controlled Substances Act (CSA) makes it unlawful for "any person knowingly or intentionally … to manufacture, distribute, or dispense" a controlled substance, "[e]xcept as authorized by this subchapter." 21 U.S.C. §841(a)(1). Under the relevant subchapter, individuals who have registered with the Attorney General to distribute controlled substances are authorized to do so "to the extent authorized by their registration." 21 U.S.C. 822(b). Under the CSA, the Attorney General also must accept the registration of a medical doctor or other practitioner if he is "authorized to dispense … controlled substances under the laws of the State in which he practices." 21 U.S.C. §823(f). Accordingly, licensed and registered physicians may lawfully prescribe controlled substances. Further, under the applicable federal regulation, 21 C.F.R. 1306.04(a) "[a] prescription is lawful … if the prescription is 'issued for a legitimate medical purpose by an individual practitioner acting in the usual course of his professional practice.'"