In the 1918 case Webb et al. v. United States, physicians George H. Webb and James W. Norris were convicted for violating the Harrison Narcotic Act of 1914 by prescribing narcotics to addicts not as a cure or treatment but merely to maintain their addiction levels. The defendants argued that they had acted within their professional practice, which was exempted from prosecution under the act; however, this argument was rejected by lower courts. The U.S Supreme Court upheld these convictions in a unanimous decision stating that such prescriptions did not fall within the scope of 'professional practice' protected by law because they served no therapeutic purpose and only perpetuated harmful addictions rather than treating any illness or condition. This ruling clarified that doctors could be prosecuted for irresponsible prescription practices under federal drug laws if those actions contributed to ongoing drug abuse instead of serving legitimate medical purposes.

The dissenting opinion in the case of Webb et al. v. United States argued that the defendants, physicians who prescribed alcohol for their patients during Prohibition, were not guilty of conspiracy to defraud the government by prescribing liquor for non-medical purposes. The dissent contended that there was insufficient evidence to prove beyond a reasonable doubt that these prescriptions were not issued in good faith and within professional bounds. It also pointed out inconsistencies in how different states interpreted and enforced national prohibition laws regarding medicinal use of alcohol, which could have led to confusion among medical practitioners about what constituted legal practice under such circumstances.