In the United States v. Moore case of 1975, the Supreme Court ruled that a physician could be prosecuted under federal law for excessively prescribing drugs outside of their professional practice. The defendant, Dr. James R. Moore was convicted by a jury in District Court for illegally dispensing methadone to patients without legitimate medical purpose and beyond the bounds of his professional practice, violating provisions within the Controlled Substances Act (CSA). On appeal, he argued that only an individual's registration status with CSA determined criminal liability not how they conducted their medical practice; thus as a registered practitioner he should be immune from prosecution under this act. However, Supreme Court rejected this argument stating that Congress intended to limit immunity to those practitioners who prescribe controlled substances in usual course of professional treatment not those using it as means for drug abuse or trafficking.

In the dissenting opinion for United States v. Moore, Justice William Rehnquist argued that the majority's decision to uphold a lower court ruling dismissing charges against a doctor accused of illegal drug distribution was misguided. He contended that the Controlled Substances Act did not exempt physicians from prosecution and emphasized that it should be up to juries, not judges, to determine whether or not an individual has violated this law. According to him, by allowing doctors who prescribe drugs without legitimate medical purpose immunity from criminal liability under federal narcotics laws would undermine efforts in combating drug abuse problem in society. The justice further criticized his colleagues' interpretation of "good faith" as too broad and subjective which could potentially lead to misuse by unscrupulous practitioners.