Fourteenth Amendment, Section 1:
All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside. No State shall make or enforce any law which shall abridge the privileges or immunities of citizens of the United States; nor shall any State deprive any person of life, liberty, or property, without due process of law; nor deny to any person within its jurisdiction the equal protection of the laws.
Justice Holmes’ characterization of the Equal Protection Clause as the
usual last refuge of constitutional arguments 1 was no doubt made with the practice in mind of contestants tacking on an equal protection argument to a due process challenge of state economic regulation. Few police regulations have been held unconstitutional on this ground.
[T]he Fourteenth Amendment permits the States a wide scope of discretion in enacting laws which affect some groups of citizens differently than others. The constitutional safeguard is offended only if the classification rests on grounds wholly irrelevant to the achievement of the State’s objective. State legislatures are presumed to have acted within their constitutional power despite the fact that, in practice, their laws result in some inequality. A statutory discrimination will not be set aside if any state of facts reasonably may be conceived to justify it. 2 The Court has made it clear that only the totally irrational classification in the economic field will be struck down, 3 and it has held that legislative classifications that impact severely upon some businesses and quite favorably upon others may be saved through stringent deference to legislative judgment. 4 So deferential is the classification that it denies the challenging party any right to offer evidence to seek to prove that the legislature is wrong in its conclusion that its classification will serve the purpose it has in mind, so long as the question is at least debatable and the legislature
could rationally have decided that its classification would foster its goal. 5 The Court has condemned a variety of statutory classifications as failing the rational basis test, although some of the cases are of doubtful vitality today and some have been questioned. Thus, the Court invalidated a statute that forbade stock insurance companies to act through agents who were their salaried employees but permitted mutual companies to operate in this manner. 6 A law that required private motor vehicle carriers to obtain certificates of convenience and necessity and to furnish security for the protection of the public was held invalid because of the exemption of carriers of fish, farm, and dairy products. 7 The same result befell a statute that permitted mill dealers without well-advertised trade names the benefit of a price differential but that restricted this benefit to such dealers entering the business before a certain date. 8 In a decision since overruled, the Court struck down a law that exempted by name the American Express Company from the terms pertaining to the licensing, bonding, regulation, and inspection of
currency exchanges engaged in the sale of money orders. 9