Last week, the Supreme Court (Court) heard oral arguments in companion cases Ruan v. United States and Kahn v. United States, concerning the application of the Controlled Substances Act (“CSA” or “the Act”) to medical practitioners. Through these cases, the Court is expected to resolve a circuit split over the role of “good faith” as a defense for medical practitioners charged with unlawfully distributing narcotics under Section 841(a) of the Act (see our previous article about the issues before the Court and the different approaches to good faith taken by the circuit courts). While arguments did not offer a clear view into the direction the Court is headed, three points of friction emerged that may inform the Court’s decision.