During that time, the Supreme Court issued several decisions invalidating federal and state statutes that sought to regulate working conditions during the Progressive Era and the Great Depression.

The period ended with West Coast Hotel Co. v. Parrish (1937), in which the Supreme Court upheld the constitutionality of minimum wage legislation enacted by Washington State.

In 1899, New York authorities indicted Joseph Lochner on a charge of violating the Bakeshop Act by permitting an employee to work more than 60 hours in one week.

He denied New York's argument that the Bakeshop Act was a necessary health measure by claiming that the "average bakery of the present day is well ventilated, comfortable both summer and winter, and always sweet smelling."

On April 17, 1905, the Supreme Court issued a 5–4 decision in favor of Lochner that struck down the New York Bakeshop Act's limits on bakers' working hours as unconstitutional.

[8] Citing its 1897 decision Allgeyer v. Louisiana, in which it had struck down a Louisiana law that banned buying shipping insurance from companies in other states on grounds that it violated the freedom to make contracts to carry out a trade or profession, the Court held that freedom of contract was a basic right covered by the protections for "life, liberty, and property" in the Fourteenth Amendment's Due Process Clause.

The right to purchase or to sell labor is part of the liberty protected by this amendment unless there are circumstances which exclude the right.The Court explained that by "circumstances which exclude the right", it meant when a state passed a law under the "police power"—the inherent authority of U.S. state governments to pass laws governing "health, safety, and morals".

[15] It is also urged ... that it is to the interest of the State that its population should be strong and robust, and therefore any legislation which may be said to tend to make people healthy must be valid as health laws, enacted under the police power.

It is made for people of fundamentally differing views ....Holmes pointed out that there were many American laws restricting citizens' freedom of contract that had never been found unconstitutional.

[19] Holmes analogized the majority's interpretation of the Fourteenth Amendment to the writings of Herbert Spencer, the 19th-century British sociologist who coined the term "survival of the fittest" and whose ideas later became associated with social Darwinism.

I think that the word liberty in the Fourteenth Amendment is perverted when it is held to prevent the natural outcome of a dominant opinion, unless it can be said that a rational and fair man necessarily would admit that the statute proposed would infringe fundamental principles as they have been understood by the traditions of our people and our law.

It does not need research to show that no such sweeping condemnation can be passed upon the statute before us.The case is famous because there is virtually universal agreement among judges and scholars that it was incorrectly decided.

The Supreme Court's due process jurisprudence over the next three decades was inconsistent, but it took a narrow view of states' police powers in several major labor cases after Lochner.

Justices James McReynolds, George Sutherland, Willis Van Devanter, and Pierce Butler emerged during the 1920s and the 1930s as the foremost defenders of traditional limitations on government power on the Supreme Court and so were collectively dubbed by supporters of the New Deal the "Four Horsemen of Reaction."

In 1937, the Supreme Court decided West Coast Hotel Co. v. Parrish, which expressly overruled Adkins and implicitly signaled the end of the Lochner era by repudiating the idea that freedom of contract should be unrestricted.

The Supreme Court sounded the death knell for economic substantive due process several years later in Williamson v. Lee Optical of Oklahoma (1955) by unanimously declaring, "The day is gone when this Court uses the Due Process Clause of the Fourteenth Amendment to strike down state laws, regulatory of business and industrial conditions, because they may be unwise, improvident, or out of harmony with a particular school of thought."

"[22] According to the Center for American Progress, a left-leaning thinktank, law professors often use Lochner, along with Plessy v. Ferguson and Korematsu v. United States, as examples of "how judges should not behave.

[24] However, it has come under harsh criticism from conservative and libertarian jurists as well because Lochner embraced substantive due process, a doctrine that was arguably at odds with the original understanding of the Constitution.

As such clauses were "deeply rooted in American history and tradition," they likely informed the original meaning of the scope and nature of the fundamental rights protected by the Fourteenth Amendment in the eyes of Lochner-era justices.

[28] However, the decision also has attracted libertarian defenders: the Cato Institute and the scholars Richard Epstein and Randy Barnett, who argue that it correctly protected economic liberty.