In the case of Cline v. Frink Dairy Company, 1926, the U.S Supreme Court ruled on a dispute involving an Oklahoma statute that regulated prices for milk and cream. The law was challenged by Frink Dairy Company and other dairy businesses who argued it violated their Fourteenth Amendment rights to due process and equal protection under the law. They claimed that setting minimum prices interfered with their ability to conduct business freely. However, District Attorney Cline defended the statute as necessary to protect public health and welfare by ensuring fair competition among dairies while maintaining quality standards for milk products. The Supreme Court sided with Frink Dairy Company ruling that although states have broad powers in regulating industries affecting public interest or safety (like utilities), they cannot arbitrarily interfere with private business models or set price controls without demonstrating a clear connection between those regulations and public welfare objectives. In this case, there was no evidence showing how fixed minimum prices would promote better quality or safer dairy products; thus, such regulation constituted an unconstitutional interference into private economic affairs.

In the dissenting opinion for Cline v. Frink Dairy Company, Justice Holmes argued that the Oklahoma statute in question did not violate the Equal Protection Clause of the Fourteenth Amendment as it was a reasonable exercise of state power to protect public health and welfare. He contended that states have broad authority to regulate businesses within their borders, especially when such regulation is aimed at protecting consumers from potential harm. In this case, he believed that Oklahoma had legitimate reasons for requiring dairy companies to maintain certain standards in order to sell milk products within its borders - namely ensuring public safety by preventing foodborne illnesses associated with unpasteurized milk. Therefore, he disagreed with majority's decision which struck down these regulations on grounds they were discriminatory against out-of-state dairies.