The police power lies within that great body of powers reserved to the states, and not conferred upon the federal government. In the very nature of things this ought to be so. If state governments were to be continued for any purpose as independent repositories of the powers which the people confer upon governments, then it was natural that in the formation of our constitutional system the protection of property and personal rights, the preservation of the public health and the promotion of the general welfare would be left to the state governments. Thus it was held in The Civil Rights Cases that even under the Fourteenth Amendment of the federal constitution prohibiting the states from making or enforcing any law " which shall abridge the privileges or immunities of citizens of the United States," and authorizing Congress to enforce this amendment by appropriate legislation, Congress could not enact a civil rights act, the object of which was to protect colored persons in the equal enjoyment with white persons of the privileges of hotels, passenger trains, theatres, barber shops, and other places of public enjoyment, entertainment, or amusement, on the ground that federal legislation "cannot properly cover the whole domain of rights appertaining to life, liberty, and property, defining them and providing for their vindication. That would be to establish a code of municipal law regulative of all privileges between man and man in society. It would be to make Congress take the place of state legislatures and to supersede them."

States in exercising this police power must keep within the limitations of federal and state constitutions, but their authority to exercise it is not conferred by the federal constitution, nor taken away by it. Such statutory provisions as were embodied in the civil rights acts may well be enacted by the states in the exercise of the police power; but they are not within the exercise of any of the enumerated powers given to Congress by the federal constitution. It may be true that the impelling motive for the adoption of the Fourteenth Amendment was the protection of the rights of the colored people recently emancipated from slavery; but the protection guaranteed was against discrimination by the states themselves and not infringement of their rights as citizens by their fellow-citizens; and it is well settled now that whatever may have been the motive for the adoption of that amendment, its provisions are general in their character and extend to all persons alike. (See, §§ 21, 259.)

Some classes of legislation enacted by Congress may be prompted by a desire to promote the general welfare of the people, as, for instance, the general protective tariff system and the legislation in reference to internal improvements; but such legislation rests for its constitutionality on powers implied from those conferred upon Congress by the federal constitution. The protective tariff laws are measures properly enacted under the express power to raise revenue and to regulate foreign commerce; and appropriations for internal improvements are justified as a legitimate exercise of powers given to Congress with reference to commerce, post offices and post roads, and like subjects. Thus obscene publications, lottery advertisements, and like objectionable matter are excluded from the mails (see below, § 104); and under the power to regulate interstate and foreign commerce the transportation of lottery tickets as articles of such commerce is prohibited. (Lottery Case.) But the federal constitution nowhere gives to Congress a general power to provide for the public welfare. The phrase "for the common defence and general welfare of the United States " appears in the clause relating to the power of Congress to lay and collect taxes, duties, and imposts (Art. I, § 8, ¶ 1), and is merely a specification of purposes - possibly a limitation on the purposes - for which money may thus be raised, not a grant of legislative power in reference to the protection of private rights. The citizens of a state, although they are also citizens of the United States, are to look to the laws and authority of their own state to determine and protect their rights with reference to each other and each other's property, and the federal authority interferes only so far as the federal constitution itself may authorize.