In the 1904 case of Olsen v. Smith, the United States Supreme Court examined whether a state law that required all butter substitutes to be colored pink was constitutional. The Minnesota legislature had passed this law with the intention of protecting consumers from being deceived by margarine manufacturers who were coloring their products yellow to resemble butter. However, Ole Oleson and other margarine producers argued that this requirement violated their Fourteenth Amendment rights because it interfered with their ability to conduct business and deprived them of property without due process of law. The court ruled in favor of Smith (the representative for Minnesota), upholding the constitutionality of the state's legislation. It found that states have broad powers under their police authority to regulate businesses in order to protect public health or prevent fraud, even if such regulations might interfere with private interests. In this instance, it determined that preventing consumer deception was a legitimate exercise of these powers.

In the dissenting opinion for Olsen v. Smith, it was argued that the majority's decision to uphold a law prohibiting non-citizens from fishing in Washington state waters violated equal protection principles under the Fourteenth Amendment. The dissent contended that this discriminatory legislation unfairly targeted foreign-born individuals and created an unjustifiable distinction between citizens and non-citizens regarding their ability to earn a livelihood through fishing. It also suggested that such laws could potentially lead to retaliatory measures by other countries against U.S. citizens abroad, thereby undermining national interests on an international scale.