The objection is made against legislation designed to limit the length of the workday that it is unconstitutional in that it restricts the freedom of contract of the worker. This objection is not urged in the case of legislation restricting the hours of labor for children, and in recent years it has ceased to be urged in the case of women workers. It is generally granted now that in the case of these two classes the state has the right under its police power of enacting such legislation.

Although it is only within recent years that American courts have been willing to grant the constitutionality of laws limiting the number of hours for women, at the present time most of the states have such legislation. This legislation usually provided for a ten-hour day with a limit of fifty-two or fifty-four hours a week. In some cases the working day is limited to nine or even to eight hours.

In the case of men the right to enact hours of labor legislation has been more stubbornly contested. Partly for this reason, and partly because of the power of labor organizations, the effort to secure a shortened workday for men has for the most part taken the direction of collective bargaining rather than legislation. But even here something has been secured by legislation. In fourteen states an eight-hour day has been secured for the workers in mines. Such work because of its peculiar nature was held to come under the police power of the state. In various other businesses in which there is a special public interest, such as smelting, electric lighting, rolling mills, bakeries, and cotton and woolen mills, there has been legislation by a few states restricting the number of working hours. In one state a ten hour day has been provided for by legislation in every "mill, factory, or manufacturing establishment," but this law is being attacked in the courts. In many of the states there are laws limiting the length of the workday for men employed on public work. In this case, however, the police power need not be invoked since the state is the employer and may make such contracts with its employees as are mutually satisfactory. Similarly, in a number of cases there has been legislation requiring that a prescribed minimum wage be paid for labor upon public works. But this legislation is not usually thought of as minimum wage legislation.