Whether Kansas could, consistently with the Fourteenth Amendment, prohibit the manufacture and sale of intoxicating liquor for beverage use, including manufacture for the maker's own use.
Holding
Yes. Kansas's prohibition was a valid exercise of the State's police power and did not deprive Mugler of liberty or property without due process or abridge a federal privilege or immunity.
Reasoning
The Court began with settled precedent recognizing that regulation or prohibition of the liquor trade ordinarily falls within a State's authority over its internal affairs. A State may protect public health, safety, and morals by restraining a traffic it reasonably regards as a source of drunkenness, disorder, poverty, and crime.
The Fourteenth Amendment did not transfer the States' traditional police power to the federal government. Although courts must invalidate legislation that has no real or substantial relation to public health, safety, or morals, or that is a palpable invasion of constitutional rights, every reasonable presumption favors a statute's validity.
Kansas could reasonably conclude that allowing private manufacture for personal beverage use would frustrate its broader prohibition scheme. The asserted right to make intoxicating drink for oneself was not a privilege of national citizenship and remained subject to the State's authority to prevent uses of property thought injurious to the community.
The Court emphasized that judges may not substitute their policy judgment for the legislature's. Because prohibition was fairly adapted to Kansas's objective of protecting the public from the recognized harms associated with intoxicating liquor, the Court could not override the legislature's determination that prohibition was necessary.