delivered the opinion of the Court.
The petitioner, a citizen of California, brought an action against the respondent in the Superior Court of the State to recover for injuries sustained in the course of his employment as a switchman. The complaint recites that the respondent, a Kansas corporation, is a common carrier by railroad in interstate сommerce, authorized to transact business in California, and that the line on which the accident occurred is a highway of interstate commerce. The cause of petitioner’s injury is alleged to have been a defective coupling apparatus upon a freight car, used in violation of the Federal Safety Appliаnce Acts. 1 The complaint does not state that, at the time of theTccident, petitioner was engaged in interstate commerce. After removal to the federal court a demurrer was filed challenging the complaint for failure to state a cause of action. The demurrer was sustained and leave -to amend refusеd. .The Circuit Court of Appeals affirmed, holding that as the petitioner, when injured, was not engaged in interstate commerce, he may seek redress only *146 under the California workmen’s compensation act. 2 The petitioner sought review by this court on the ground that the decision conflicts with adjudications of the California courts sustaining the right to maintain an action for damages in like circumstancеs. We granted certiorari.
-The Safety Appliance Acts impose an absolute duty upon an employer and prescribe penal sanctions for breach. The earliest, that of 1893, affected only cars .which were being used in interstate commerce. By the Act of 1903 the duty was extended to all cars used upon any railroad which is a highway of interstate commerce. 3 The absolute duty imposed necessarily supersedes the common law duty of the employer. But, unlike the Federal Employers’ Liability Act, which gives a right of action for negligence, the Safety Appliance Acts leave the nature and the incidents of the remedy to the law of the states. 4 The Safety Appliance Acts modify the enforcement, by civil action, of the employe’s common law right in only one aspect, namely, by withdrawing the defense of assumption of risk. 5 They do not touch the common or statute law of a state governing venue, limitations, contributory negligence, or recovery for death by wrongful act. 6
*147
In
Texas & Pacific Ry. Co.
v.
Rigsby,
As respects an injury occurring during the course of employment in intrastate activities on'a highway of interstate commerce, the question has arisen whether a stаte may substitute workmen’s compensation for the common law or statutory action whereby damages could have been recovered for violation of the Safety Appliance Acts. A number of courts have interpreted the discussion in the Bigsby case as a denial of the power of the states to make the substitution. 7
This court' hаs recently reaffirmed the principle that the Safety Appliance Acts do not give a right of action
*148
for their breach but leave the genesis and regulation of such action to the law of the states. In
Moore
v.
Chesapeake
&
Ohio Ry. Co.,
In
McMahon
v.
Montour R. Co.,
California is at liberty to afford any appropriate remedy for breach of the duty imposed by the Safety Appliance Acts. Her choice in the matter raises no federal question and the federal courts are as much bound as those of *149 California to conform to the remedial procedure she has adopted. There is nothing to prevent her prescribing workmen’s compensation, elective or compulsory, in lieu of a common law or statutory action for disability or death arising from a breach of the duty imposed. The question is: has California, as the petitioner insists, excepted from the scope of her workmen’s cоmpensation act injuries sustained by an employe engaged in intrastate transportation? The Circuit Court of Appeals thought she had not. Whether this conclusion is right depends upon the force and effect of two District Court of Appeal decisions, which the Supreme Court of the State'refused to review.
Ballard
v.
Sacramento Northern Ry. Co.,
The railway company insisted that the state workmen’s compensation act afforded the only redress for the decedent’s death. In overruling the contention the court cited
Smithson
v.
Atchison T. & S. F. Ry. Co.,
174 Cal.
*150
148;
“By subdivision ‘C of section 69 of the Workmens’ Compensation Act, it is expressly provided that where interstate commerce questions are presented, resort to the courts is not prohibited.”
In
Walton
v.
Southern Pacific Co.,
8 Cal. App. (2d) 290;
“The appellant’s contentions that the sole remedy of an employee of a common carrier, engaged in interstаte transportation, or, in this case, of his personal representative, where, at the time of the injury, the employee was not engaged in interstate transportation, but under circumstances where there has been a violation of duty imposed by the Boiler Inspection Act, is under the State Workmen’s Compensation Act are untenable (St. 1917, p. 831, as amended). The evidence here shows that the accident happened on a highway of interstate commerce. ...
“Undér the authority of
Ballard
v.
Sacramento Northern Railway Co.,
If these decisions of intermediate courts of appeal, and the refusal of the Supreme Court of California to review them, amount to no more than a judicial construction of the сompensation act as having, by its terms, no application in the circumstances, they are binding authority in federal courts. 12 If, on the other hand, the state courts excluded railroad employees injured in intrastate operations from the benefits of the compensation act, not as a matter of construction of the statute, but because they thought the Safety Appliance Acts required the State to *152 afford a remedy in the nature of an action for damages, then the court below was right in disregarding that errone,ous construction of the federal acts. 13
In the Ballard case the court thought the Safety Appliance Acts, in addition to imposing a duty, afforded a remedy, and to deny that remedy would be to disregard the mandate of the federal statutes. It was proper, in this view, to construe.the language of the compensation act accordingly. In the Walton case, while holding the Boiler Inspection Act irrelevant upon the question of the appropriate remedy, the court denied the aрplication of the workmen’s compensation law, upon the authority of the Ballard case..
The Supreme Court of the State refused to review either of the cases although this court had recently defined the scope of the Safety Appliance Acts in the Moore and Gil-vary cases.. If we were convinced that the court acted solely upon а construction of the workmen’s- compensation law, uninfluenced by the decisions following the supposed Authority of the Rigsby case, we should not hesitate to hold United States courts bound by such construction of the state statute. But the terms of the state compensation law, and the California decisions construing it, lead us to doubt that this is so.
The act, in § 6, provides: 14
“(a) Liability for the compensation provided by this act, in lieu of any other liability whatsoever to any person, shall, without regard to negligence, exist against an employer for any injury sustained by his employees arising out of and in the course of the employment . . .
“(b) Where such conditions of compensation exist, the right to recover such cоmpensation, pursuant to the provisions of this act, shall be the exclusive remedy against the employer for the injury or death; ...”
*153 Section 69 provides: 15
“(c) Employers engaged in interstate commerce. This act shall not be construed to apply to employers or employments which, accordirig to law, are so engaged in interstate commerce as not to be.subject to the legislative powеr of the state, or to employees injured while they are so engaged, except in so far as this act may be permitted to apply under the provisions of the Constitution of the United State's or the acts of Congress.”
Thus, by its plain terms, the compensation law embraces- injuries to an employe circumstanced as was the pеtitioner' in this case. Employers or employments in interstate commerce (the phrase used) obviously signifies situations covered by the Federal Employers’ Liability Act which , gives a right of action for breach. The phrase does not exclude injuries consequent upon violation of the Safety Appliance Acts in intrastate commеrce and the remainder of the section evinces a determination that the compensation act shall govern the rights of employes in interstate commerce so far as permissible-under the federal laws. 16 As has been shown, these laws do not forbid its application in the instant case.
■ The Supreme Court of California has rеpeatedly declared the purpose and effect of the compensation act.
“The enactment substitutes a new system of rights and obligations for the common-law rules governing the liability of employers'for injuries to their workmen. The change thus made is radical, not to say revolutionary. In place of the old action, in which thе employer was liable only if he, or someone representing him, .had been guilty of negligence or misconduct, the new law impqsés upon' the employer a liability for any accidental injuries to his employees arising out of the employment—a liability not *154 conditioned upon any negligence of the employer, or any want of negligence on the part of the employee.” 17
“The California Workmen’s Compensation Act provides the only means by which an injured employee can recover compensation from his employer for injuries received in the course of and arising out of his employmént, and it abrogates the common-law liability of the master fоr such injuries in the cases to which it is applicable.
(Netherlands American Steam Nav. Co.
v.
Gallagher,
We are not persuaded that if the state courts had thought that California was free to ordain a plan of workmen’s compensation in lieu of an action for damages for' breach of the duty imposed by the Safety Appliance Acts they would have restricted the scope of the Workmen’s *155 Compensation Act as was done in the Ballard and Walton cases. A definite and authoritative decision that its scope is so limited, and that the appropriate remedy under state law is an аction for damages, will, of course, be binding upon federal courts. In the absence of such a pronouncement we are of opinion the Circuit Court of Appeals committed no error in construing the Workmen’s Compensation Act as affording the only , remedy available to the petitioner.
The judgment is
Affirmed.
Notes
March 2, 1893, c. 196, 27 Stat. 631, U. S. C. Tit. 45, §§ 1-7; March 2, 1903, c. 976, 32 Stat. 943, U. S. C. Tit. 45, §§ 8-10; April 14, 1910, c. 160, 36 Stat. 298, U. S. C. Tit. 45, §§ 11-16.
78 F. (2d) 450.
Section 1, U. S. C. Tit. 45, § 8;
Southern Ry. Co.
v.
United States,
Moore
v.
Chesapeake & O. Ry. Co.,
Minneapolis, St. P. & S. S. M. Ry. Co.
v.
Popplar,
St. Louis, I. M. & S. Ry. Co.
v.
Taylor,
Ross
v.
Schooley,
McMahan
v.
Montour R. Co.,
April 22, 1908, c. 149, 35 Stat. 65, U. S. C. Tit. 45, §§ 51-59.
April 5, 1910, c. 143, 36 Stat. 291, U. S. C. Tit. 45, §§ 56-59.
U. S. C. Tit. 45, §§ 22-34.
Burns Mortgage Co.
v.
Fried,
Red Cross Line
v.
Atlantic Fruit Co.,
II Deering’s General Laws of California, pp. 2276-7.
II Deering’s General Laws of California, p. 2316.
Compare
Boston & M. R. Co.
v,
Armburg,
Western Indemnity Co.
v.
Pillsbury,
Alaska Packers Assn.
v.
Industrial Accident Comm’n,
