From Justice McReynolds, the author of the decision in U.S. v. Miller:
Probably most of those accelerated to prison under the present Act will be unfortunate addicts and their abettors; but even they live under the Constitution. And where will the next step take us? When the Harrison Anti-Narcotics Law became effective probably some drug containing opium could have been found in a million or more households within the Union. Paregoric, laudanum, Dover’s Powders, were common remedies. Did every man and woman who possessed one of these instantly become a presumptive criminal and liable to imprisonment unless he could explain to the satisfaction of a jury when and where he got the stuff? Certainly, I cannot assent to any such notion, and it seems worthwhile to say so.
–Justice McReynolds writing in Casey v. United States, 276 U.S. 413, 421 (1928), quoted in footnote 24 of “The Peculiar Story of United States v. Miller,” by Brian L. Frye.