agreement with the seller, but by virtue of a rule made by an association of which he is a member." Again, the Supreme Court of the State says: "Petitioner insists that by prohibiting him from making the deduction of one hundred pounds his property is taken without due process of law. We agree with the Attorney General that he has reversed the conditions. To strike down this act will be to permit him to continue to take the shipper's property without due process of law, and without any compensation therefor. Without further elaboration, we are of the opinion that this act is a valid one and it is wisely aimed to prevent unjust and unfair practice and to repeal and nullify a rule of the Board of Trade which is unjust and unfair and contrary to good morals and fair dealings, and the act offends against no provision of the Constitution." Reference has been made to the fact that the Board of Trade of Kansas City is a voluntary association of individuals who perform great service to the public, and that its purpose is to enforce, as between its members, a high standard of business dealings. Let all this be granted, and yet it must be held that the Board, in the management of its affairs, has such close and constant relations to the general public, that the conduct of its business may be regulated by such means, not arbitrary or unreasonable in their nature, as may be found by the State necessary or needful to protect the people against unfair practices that may likely occur from time to time. Such regulations do not, in any true sense, interfere with that "liberty of contract" which the individual members of the Board of Trade are undoubtedly entitled, under the Constitution to enjoy, without unnecessary interference from government; for, the liberty of contract which that instrument protects against invasion by the State is subject to such regulations of the character just stated, as the State may establish for the protection of the public and the promotion of the general welfare. If such state regulations are not unreasonable, that is, not simply arbitrary nor beyond the necessities of the case, they are not forbidden by the Constitution of the United States. We so adjudge on both principle and authority. The judgment of the Supreme Court of Missouri is MR. JUSTICE MCKENNA concurring. Affirmed. THE CHIEF JUSTICE and myself concur in the judgment solely on the ground that it is competent for the State of Missouri to provide that, in the absence of an express contract to which the owner of the articles sold on the Board is a party, the rule of the Kansas City Board of Trade shall not prevail. BRODNAX v. STATE OF MISSOURI. ERROR TO THE SUPREME COURT OF THE STATE OF MISSOURI. No. 598. Argued December 14, 1910.-Decided January 9, 1911. In this case, as the statute shows on its face that the subject regulated needed to be regulated for the protection of the public against fraudulent practices to its injury, this court is not prepared to declare that the State has acted beyond its power or the necessities of the case. While it is the duty of the Federal courts to protect Federal rights from infringement, they should not strike down a police regulation of a State that does not clearly violate the Federal Constitution; they cannot overthrow police legislation because they consider it unwise or inexpedient. House v. Mayes, ante, p. 270. Although the due process clause of the Fourteenth Amendment secures liberty of contract, it does not confer liberty to disregard lawful police regulations of the State established by the State for all within its jurisdiction. Argument for Plaintiff in Error. 219 U. S. A classification of persons keeping places where stocks, bonds and such commodities as grain, petroleum and cotton are dealt in for future and not actual delivery, is a reasonable one and not a denial of equal protection of the laws. The fact that commodities in course of transportation in interstate commerce are dealt in at certain places does not render a state police statute regulating sales, and imposing stamp tax on records of transactions thereat, which is otherwise valid, an unconstitutional regulation of interstate commerce. Hatch v. Reardon, 204 U. S. 502. It is not a violation of the due process, or equal protection, clause of the Fourteenth Amendment, or an unconstitutional regulation of interstate commerce, for a State to prohibit the keeping of a place where purchases or sales are made of stocks, bonds, petroleum, grain, cotton, etc., on margins or otherwise, not paid for or delivered at the time, without record of sale and stamp tax, by a statute applicable to all persons keeping such places, and so held as to the Missouri statute to that effect of March 8, 1907. THE facts, which involve the constitutionality of a statute of Missouri prohibiting the keeping of places for dealing in stocks, bonds and commodities for future delivery except under certain conditions, are stated in the opinion. Mr. Frank Hagerman, with whom Mr. Kimbrough Stone was on the brief, for plaintiff in error: The act is not limited to all sales of any particular commodity, but are those of particular things, i. e., corporate bonds and stocks, petroleum, cotton, grain and provisions. No provision is made for the collection of the tax from any person or property. For its enforcement, reliance must be placed solely upon the coercion flowing from the criminality involved in a violation of its terms. As against the keeper, as each plaintiff in error was, this act must, if at all, be sustained as a police regulation, and as such it is void because interfering with the liberty of contract and because it is discriminatory. The Fourteenth Amendment secures to everyone the right to carry on a business and to make all contracts 219 U. S. Argument for Plaintiff in Error. needful for the purpose. Allgeyer v. Louisiana, 165 U. S. 578, 589; Holden v. Hardy, 169 U. S. 366, 390; Lochner v. New York, 198 U. S. 45, 53; Adair v. United States, 208 U. S. 161, 172. This right to contract is of no value if there be no power to extend credit, or if one to buy or sell must have immediate delivery. The police power of the State cannot be exercised unreasonably nor in an arbitrary manner, and whether it has been or not is a question solely for the courts. Cases supra. The act considered as a police regulation is discriminatory. Gulf, C. & S. F. R. Co. v. Ellis, 165 U. S. 150; Cotting v. Godard, 183 U. S. 79; Connolly v. Union Sewer Pipe Co., 184 U. S. 540; State v. Loomis, 115 Missouri, 307, 314; State v. Julow, 192 Missouri, 163, 177; State v. Walsh, 136 Missouri, 400, 405; State v. Mikisek, 225 Missouri, 561, 577. It singles out certain articles, the sale of which at certain places is lawful and not harmful, but absolutely necessary, and attempts to classify those who there sell on credit or for future delivery, as distinguished from those who sell the same articles for the same prices for cash and make present delivery. No case has ever gone to the extent of sustaining such classification for any purpose whatever. Such classification is arbitrary, artificial and fanciful, and does not rest upon a distinction differentiating the particular persons to be affected. Gray on Limitation of Taxing Power, § 1435; Southern Ry. Co. v. Greene, 216 U. S. 406, 417; People v. Mensching, 187 N. Y. 8; Barbier v. Connolly, 113 U. S. 27; Gulf, C. & S. F. R. Co. v. Ellis, 165 U. S. 150; Yick Wo v. Hopkins, 118 U. S. 356; Raymond v. Chicago Traction Co., 207 U. S. 20, 37; Tiernan v. Rinker, 102 U. S. 123; Webber v. Virginia, 103 U. S. 344; Walling v. Michigan, 116 U. S. 446; State v. Gorbroski, 111 Iowa, 496; O'Keefe v. Summerville, 190 Massachusetts, 110. Argument for Plaintiff in Error. 219 U. S. See also where laws have been held to be discriminatory when they impose a tax only upon foreign unnaturalized laborers, Juniata Limestone Co. v. Fagley, 187 Pa. St. 193; Fraser v. Conway, 6 Pa. Dist. R. 555; on peddlers, except those "persons who have served in the Union army or navy," State v. Garbroski, 111 Iowa, 496; on taxable inhabitants who had not paid a previous assessment, State v. Township, 36 N. J. L. 66; on peddlers and transient merchants but not upon permanent merchants doing the same kind of business, State ex rel. v. Parr, 109 Minnesota, 147; State v. Wagener, 69 Minnesota, 206; upon peddlers in the State other than those of a particular county, Commonwealth v. Snyder, 182 Pa. St. 630; requiring a license from each individual plumber, but providing that the license of one member of a firm or manager of a corporation should be sufficient, State v. Benzenburg, 101 Wisconsin, 172; State v. Gardner, 58 Ohio St. 599; providing that a license fee for a place upon one street of a city shall be higher than when it is upon another, Harrodsburg v. Renfro (Ky.), 58 S. W. Rep. 695. And see Lassen Co. v. Cone, 72 California, 387. The act is unconstitutional as regulating interstate commerce. This court will look through forms to the substance of things and if in substance there is any interference, state legislation so interfering must fall, no matter how general its form and even though interstate transactions are not specifically mentioned. West. Un. Tel. Co. v. Coleman, 216 U. S. 1; Galveston, H. & T. R. Co. v. Texas, 210 U. S. 217; Pullman Co. v. Kansas, 216 U. S. 56; International Book Co. v. Pigg, 217 U. S. 91. If the act be treated as an occupation or license tax, or one for facilities used for such sale, it is still in substance a tribute laid upon property engaged in interstate commerce. Bivin v. Maryland, 12 Wheat. 419; Robbins v. Shelby County Taxing District, 120 U. S. 489; Lyng v. |