delivered the opinion of the court.
Alleging that in the month of December, 1913, he was in the employ of the Texas Power apd Light Company-in the
*154
State of Texas, and while so employed received serious personaL'-'injüiies 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 Staté to recover his damages. The defendant interposed an answer in the nature of a plea in abatement setting up that at the túne óf the accident and at the commencement of the action défendant 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 compеnsation provided by'the Texas Workmen’s Compensation Act, which was approved April 16, 1913", and took effect on the first day of September in that year (c. 179, Acts’ of 33d Legislature), 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 Unitеd States. The exception was overruled, the plea, in- abatement sustained, aiid the action dismissed. On appeal to the court of civil appeals it was at first held that, the judgment-must be reversed (
*155 Thus we have presented, from the standpoint of an objecting employee, the questiоn 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, derivеd 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 employees, or on account of death resulting from such injuries, is to be paid. This is a stated compensation, fixed with relation to thе employee’s 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, whéther 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 employee, or his death occasioned,by such injuries, when due to the negligence of the employer or his servants; it being declared that the employee of a subscribing employer, or his reprеsentatives or beneficiaries in case of his deáth, shall have no cause of action against the employer for damages, except where a death is caused by the willful act or omission or gross negligence of the employer. Employers who do not become subscribers are subject as before to suits for damages based on negligencе for injuries to employees or for death resulting therefrom; and are deprived of the so-called “common law defenses” of fellow servant’s negligence and assumed risk, and also of' contributory *156 negligence as an absolute defense,, it being provided that for contributory negligence damages' shall be diminished except where the employer’s violation of a statute enacted for the safety of employees contributes to the injury or death; but that where the.injury is caused by the willful intention of the employee to bring it about the employer may.defend on that.ground. Every employer becoming á subscriber to the insurance association is required to give written or printed notice to all his employees that he has provided for the payment by the association of compensation for injuries received by them in the course of their employment. Under certain conditions an employer holding, a liability policy issued by an insurance company lawfully transacting such business within the State is to. be deemed a subscriber within the meaning of the act. There are administrative provisions, including procedure for the determination of disputed claims. By § 2 of Part 1 it is enacted as follows: “The provisions of this Act shall not apply to actions to recover, damages for the personal injuries or for death resulting from personal injuries sustained by domestic servants, farm laborers, nor to ' the employees of any person, firm or corporation operating any railway as a common carrier, nor to laborers engaged in working for á cotton gin, nor to employees of any person, firm or corporation having in his or their employ not more than five employees.”
Following the order adopted in the argument of plaintiff in error, we deal first with the contention that the act amounts to а denial of the equal protection of the laws. This is based in part upon tfie classification Tesulting from the provisions of -the section just quoted, it being said that employees of the excepted classes are left entitled to certain privileges which by the act are denied to-employees of the non-excepted classes, without reasonable basis for the distinction.
Of course plaintiff in error, not being an employee in-
*157
any of the excepted classes, would not be heard to . assert any grievance they might have by reason of being excluded from the operation of the act.
Southern Ry. Co.
v.
King,
• However, we are clear that the classification can not be held to be arbitrary and unreasonable. The Supreme Court of Texas in sustaining it said (
There is a strong presumption that a legislature understands and correctly appreciates the needs of its own people, that its laws are directed to problems madе manifest by experience, and that itsv discriminations are based upon adequate grounds. The equal protection clause does not require that state laws shall cover the éntire field of proper legislation in a single enactment. If one entertained the view that the act might as well have been extended to other classes of employment, this would not
*158
amount to a constitutional objection.
Rosenthal
v.
New York,
The burden being upon him who attacks a law for unconstitutionality, the courts need not be ingenious in searching for grounds of distinction .to sustain a classification that may be subjected to criticism. But in this case adequate grounds are easily discerned. As to the exclusion of railroad employees, the existence of the Federal Employers’ Liability Act of April 22, 1908, с. 149, 35 Stat. 65; c. 143, 36 Stat. 291, applying exclusively as to employees of common carriers by rail injured while employed in interstate commerce, establishing liability for negligence and exempting from liability in the absence "of negligence in all cases within its reach
(New York Central R. R. Co.
v.
Winfield,
The exclusion of farm laborers and domestic servants from the compulsory scheme of the New York Workmen's Compensation Act was sustained in
New York Central R. R. Co.
v.
White,
The exclusion of employees where not more than four or five aré under a single employer is common in legislation of this .character, and. evidently permissible upon the ground that the conditions of the industry are different and the hazards fewer, simpler, and more easily avoided where so fеw are employed together; the legislature, of course, being the proper judges to determine precisely where the line should be drawn. Classification on this basis was upheld, in Jeffrey Mfg. Co. v. Blagg, 235 U. S. 571, 576-577, and has been sustained repeatedly by the state courts. State v. Creamer, 85 Ohio St. 349, 404-405; Borgnis v. Falk Co., 147 Wisconsin, 327, 355; Shade v. Cement Co., 93 Kansas, 257, 259; Sayles v. Foley, 38 R. I. 484, 491, 493.
The discrimination that results from the operation of the *160 act as between the employees of different .employers engaged in the same kind of work, where one employer becomеs a subscriber and another does not, furnishes no ground of constitutional attack upon the theory that there is a denial of the equal protection of the laws. That the acceptance of such a system may be made optional is too plain for question; and it necessarily follows that differences arising from the fact that all of those to whom the option is open do not accept it must be regarded as the natural and inevitable result of a free choice, and not as a legislative discrimination. .They stand upon the same fundamental basis as other differences in the conditions of employment arising from the variant exercise by employers and employees of their right to agree upоn the terms of employment. And see Borgnis v. Falk Co., 147 Wisconsin, 327, 354; Mathison v. Minneapolis Street Ry. Co., 126 Minnesota, 286, 294.
In recent years many of the States have passed elective workmen’s compensation laws not differing, essentially from the one here in question, and they have been sustained by well-considered opinions of the state courts of last resort against attacks based upon all kinds of constitutional objections, including allеged denial of the equal protection of the laws; usually, however, from the standpoint of the employer.
Sexton
v.
Newark District Telegraph Co.,
84 N. J. L. 85; 86 N. J. L. 701;
Opinion of Justices,
209 Massachusetts, 607;
Young
v.
Duncan,
218 Massachusetts, 346;
Borgnis
v.
Falk Co.,
147 Wisconsin, 327;
State
v.
Creamer,
Stress is laid upon the point that the Texas act, while optional to the employer, is compulsory as to the employee of a subscribing employer. Our attention is not called to any express provision prohibiting a voluntary agreement bеtween á subscribing employer and one or more of his employees taking them out of the operation of the act; but probably such an agreement might be held by the courts of the State to be inconsistent with . the general policy of the act; the supreme court, in the case before us, did not intimate that such special agreements would be permissiblе; and hence it is fair to assume that all who remain in' the employ of a subscribing employer, with'notice that he has provided for payment of compensation by the association or by an authorized insurance company, will be bound by the provisions of the act.
But a moment’s reflection will show the impossibility of giving an option both to the employer and to the employee and enabling them to exercise it in diverse ways. The provisions of the act show that the legislative purpose is that it shall take effect only upon acceptance by both employer and employee. The, former accepts by becoming a subscriber; the latter by remaining in the service of the employer after notice of such acceptance. And we see in this no ground for holding that 'there is a denial of the equal protection of the laws as between employer and employee. They stand in different relations to the common undertaking, and it was permissible to recognize this in determining how they should accept or reject the new system. The employer provides the plant, the organization,, the capital, the credit, and necessarily must control- and manage the operation. In the nature of things his contribution has less mobility than that of the employee, who may . go from place to place seeking *162 satisfactory employment, while the employer’s plant and business are comparatively, even if not аbsolutely, fixed in position. Again, in order that the new scheme of compensation .should be a success, the legislature deemed it proper, if not essential, that the payment of compensation to the injured employees or their dependents should be rendered secure, and the losses to individual employers distributed, by a system of compensation insurаnce, in which it was deemed important that all employees of a given employer should be treated alike. Still further, there áre reasons affecting the contentment of the employees and the discipline of the force, rendering it desirable that all serving under a common employer should be subject to a single rüle as to compensation in the еvent of injury or death arising in the course of the employment. These and other considerations that might be suggested fully justified the legislative body of the ■ State in determining that acceptance of the.new system should rest upon the initiative of the employer, and that any particular employee who with notice of the employer’s acceptancе dissented from the resulting arrangement should be required to exercise his option by withdrawing from the employment. The relation of employer and employee being a voluntary relation, it was well within the power of the State to permit employers to accept or reject the new plan of compensation, each for himself, as a part оf the terms of employment; and in doing this there was no denial to employees of the equal protection of the laws within the meaning of the Fourteenth Amendment.
This disposes of all contentions made under the equal protection clause.
It is argued further that there is a deprivation of liberty and property without due process. of law in requiring employees, willingly or unwillingly, to accept the new system where their employer has adopted it. Of course there is no suggésüon of a deprivation of vested property
*163
in the present case, since the law was passed in April and took effect in September, while the plaintiff’s injuries were received in the following December, after he. had been notified of his employer’s acceptance of the act. What plaintiff has lost, therefore, is only a part of his liberty to make such contract as he pleased with a particular employer and to pursue his employment under the rules of law that previously had obtained fixing responsibility upon the employer for any personal injuries the plaintiff might sustain through the negligenсe of the employer or his agents. But, as has been held so often, the liberty of the citizen does not include among its incidents any vested right to have the rules of law remain unchanged' for his benefit. The law of master and servant, as a body of rules of conduct, is subject to change by legislation in the public interest. The definition of negligence, contributory negligence, аnd assumption of risk, the effect to be given to them, the rule of
respondeat
superior, the imposition of liability without fault, and the exemption from liability in spite of fault — all these, as rules of conduct, are subject to' legislative modification. And a plan imposing upon the employer responsibility for making compensation for disabling or fatal injuries irrespective of the question of fault, and requiring the employee to assume all risk of damages over and above the statutory schedule, when established as a reasonable substitute for the legal measure of duty and responsibility previously existing, may be made compulsory upon employees as well as employers.
New York Central R. R. Co.
v.
White,
All objections to the act on constitutional grounds being found untenable, the judgment under review is
Affirmed.