[249 U.S. 152, 153] Mr. Charles B. Braun, of Waco, Tex., for plaintiff in error.

Messrs. Harry P. Lawther and Alexander Pope, both of Dallas, Tex., for defendant in error.

Mr. Justice PITNEY delivered the opinion of the Court.

Alleging that in the month of December, 1913, he was in the employ of the Texas Power & Light Company in the [249 U.S. 152, 154] state of Texas, and while so employed received serious personal injuries through the bursting of a steam pipe due to the negligence of his employer and its agents, Middleton sued the company in a district court of that state to recover his damages. The defendant interposed an answer in the nature of a plea in abatement setting up that at the time of the accident and at the commencement of the action defendant was the holder of a policy of liability and compensation insurance, issued in its favor by a company lawfully transacting such business in the state, conditioned to pay the compensation provided by the Texas Workmens Compensation Act, which was approved April 16, 1913, and took effect on the 1st day of September in that year (chapter 179, Acts of 33d Legislature, [Vernons Sayles Ann. Civ. St. 1914, arts. 5246h-5246zzzz]) of which fact the plaintiff had proper and timely notice as provided by the act; and that no claim for the compensation provided in the act with respect to the alleged injury had been made by plaintiff, but on the contrary he had refused to receive such compensation, with other matters sufficient to bring defendant within the protection of the act. Plaintiff took a special exception in the nature of a demurrer, upon the ground (among others) that the act was in conflict with the Fourteenth Amendment to the Constitution of the United States. The exception was overruled, the plea in abatement sustained, and the action dismissed. On appeal to the Court of Civil Appeals it was at first held that the judgment must be reversed (178 S. W. 956); but upon an application for a rehearing the constitutional questions were certified to the Supreme Court of the state. That court sustained the constitutionality of the law (108 Tex. 96, 185 S. W. 556); and in obedience to its opinion the Court of Civil Appeals set aside its former judgment and affirmed the judgment of the district court. Thereupon the present writ of error was sued out under section 237, Judicial Code (Act March 3, 1911, c. 231, 36 Stat. 1156), as amended by Act of September 6, 1916, c. 448, 2, 39 Stat. 726 (Comp. St. 1214). [249 U.S. 152, 155] Thus we have presented, from the standpoint of an objecting employe, the question whether the Texas Employers Liability Act is in conflict with the due process and equal protection provisions of the Fourteenth Amendment.

The act creates an employers insurance association, to which any employer of labor in the state, with exceptions to be mentioned, may become a subscriber; and out of the funds of this association, derived from premiums on policies of liability insurance issued by it to subscribing members and assessments authorized against them if necessary, the compensation provided by the act as due on account of personal injuries sustained by their employes, or on account of death resulting from such injuries, is to be paid. This is a stated compensation, fixed with relation to the employes average weekly wages, and accrues to him absolutely when he suffers a personal injury in the course of his employment incapacitating him from earning wages for as long a period as one week, or to his representatives or beneficiaries in the event of his death from such injury, whether or not it be due to the negligence of the employer or his servants or agents. Such compensation is the statutory substitute for damages otherwise recoverable because of injuries suffered by an employe, or his death occasioned by such injuries, when due to the negligence of