delivered the opinion of the Court.
In this workmen’s compensation appeal,
1
the employer and insurer (the appellants) contend that the lower court’s interpretation of § 67 (6) of the Workmen’s Compensation Act, Maryland Code (1957, 1964 Repl. Vol., 1975 Cum. Supp.), Art. 101 deprived them of due process of law in contravention of the fourteenth amendment. Section 67 (6),
2
as interpreted
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in
Giant Food, et al. v. Gooch,
The pertinent facts are as follows: Brenda Higgins, an employee of the Edgewood Nursing Home, was shot and killed by her estranged paramour while she was at work. A workmen’s compensation claim for dependency benefits was filed on behalf of Brenda’s infant daughter, Dionne. The commission concluded that Brenda’s death was compensable under the Act and that Dionne was totally dependent upon Brenda at the time of her death.
An appeal was thereafter taken to the Superior Court of Baltimore City and heard on the record. In a memorandum filed with the court, the appellants claimed that to interpret § 67 (6) to permit recovery in the absence of a causal connection between the death and the employment, other than mere occurrence in the course of employment, would be repugnant to the fourteenth amendment because it would make the employer “an involuntary insurer of the life and health of his employees under circumstances where such liability would not rest upon the employer-employee relationship.” The court affirmed the commission; it held, relying upon Gooch, that Brenda’s death was compensable under § 67 (6) of the Act and that the evidence established that Dionne was totally dependent upon her mother at the time of her death. It did not address the constitutional issue raised by the appellants.
In reasserting their constitutional argument before us appellants contend that Brenda’s death was not causally connected with her employment, and was in no sense due to inherent conditions of her work. Consequently, they argue, the lower court’s interpretation of § 67 (6) requires an employer gratuitously to insure the life of its employees against non-work related hazards and therefore *425 unconstitutionally interferes with the employer’s right freely to contract with its employees. No authority is cited in support of the appellants’ argument; indeed, the appellee is so unimpressed with the argument that she totally ignores it in her brief.
In
Gooch,
as here, the assault upon the employee did not arise out of the employment but occurred in the course of it for a reason not causally connected with the employment. Gooch was shot on the employer’s parking lot by a person who mistakenly believed that he was romantically involved with his wife. The Gourt traced the history underlying § 67 (6) and, interpreting that section in light of § 15, concluded that the legislature intended to create a special classification for employees injured by the wilful or negligent act of a third person; as to that classification of compensable injuries, there was no requirement that the injury arise out of the employment but only that it be “directed against an employee in the course of his employment.” The Court reviewed a spate of its earlier cases involving injuries inflicted upon employees, either wilfully or negligently, by third parties and noted that some confusion existed in determining whether the injuries arose out of the employment. It said that prior to 1951, when § 67 (6) was amended to its present form, an injury to an employee inflicted by a third person in the course of the employment, either wilfully or negligently, was compensable if the danger of such injury was an incident of the special conditions of the employment — that is, if it arose out of the employment — but that such an injury was not compensable if it was not attributable to the working environment — that is, did not arise out of the employment. The Court concluded that by enacting § 67 (6) the legislature “intended to broaden the scope of the compensation statute to include as compensable an injury not attributable to the working environment provided it was incurred in the course of employment.”
3
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The Workmen’s Compensation Act was passed in the exercise of the police power of the State to protect workers and their families from the hardships inflicted by work-related injuries.
Mazor v. State, Dep’t of Correction,
In the exercise of the police power the State may lawfully impose such burdens and restraints on private rights as may be reasonably necessary and proper to secure the general welfare.
Bureau of Mines v. George’s Creek, supra; Md. Bd. of Pharmacy v. Sav-A-Lot, supra; LaRoque v. Co. Commissioners,
A statute enacted under the police power carries with it a strong presumption of constitutionality and the party attacking it has the burden of affirmatively and clearly establishing its invalidity; a reasonable doubt as to its constitutionality is sufficient to sustain it.
Gino’s v. Baltimore City,
The appellants recognize that freedom to contract in connection with the employer-employee relationship is not absolute; that it may be restricted consistent with due process requirements; and that the legislature has a wide field of discretion in legislating to promote the public interest. They simply suggest that a workmen’s compensation law imposing liability upon an employer which does not rest upon the employer-employee relationship constitutes an unconstitutional interference with the employer’s right of
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freedom to contract. They also suggest that § 67 (6) is unconstitutional as applied because it requires the employer to pay compensation for an injury inflicted by a third person unrelated to the employee’s work, presumably for the reason that it takes their property without due process of law. In support of these arguments, the appellants place total reliance on the vintage Supreme Court cases of
Arizona Copper Co. v. Hammer,
In Arizona Copper, the Supreme Court upheld the constitutionality of an early workmen’s compensation law covering injuries to employees arising out of and in the course of the employment and due to inherent conditions of the work. In holding that the law was a permissible exercise of the State’s police power, the Court found no violation of . an employer’s right to contract with respect to the terms and conditions of employment. The Court did not consider whether due process requirements would be offended in the absence of a statutory provision for a causal connection between the injury and the employment. The appellants draw solace from this case by reasoning that the fundamental right of freedom to contract would have been unconstitutionally impaired had the statute not required that the injury arise out of the employment and be due to its inherent conditions. Nothing in Arizona Copper even remotely supports this convoluted reasoning.
West Coast Hotel
involved a state statute authorizing the fixing of minimum wages for women and minors. The Supreme Court upheld the statute as a permissible exercise of the police power and hence not violative of the fourteenth amendment right of freedom of contract. Indeed, the case supports the principle that freedom to contract is not an unqualified right, and that the police power may be exercised, consistent with due process requirements, with respect to contracts between employers and employees.
See generally Nebbia v. New York,
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More in point is
Cudahy Co. v. Parramore,
We think the employer’s obligation under § 67 (6) to pay compensation on behalf of an employee injured in the course of his employment by the wilful or negligent act of a third party does rest upon the employer-employee relationship. The injury is work-related in the sense that even though it arose for personal reasons not attributable to the working environment, it occurred within the course of employment on the employer’s premises at a time when the employee was obliged to be present and at work; in other words, the employee’s presence at the nursing home when the peril struck was a necessary part of her employment and the injury was inflicted in the course of that employment. In view of this nexus, and because the appellants have failed to carry the burden of establishing the invalidity of § 67 (6), we think the strong presumption of constitutionality afforded to the statute has not been overcome. It may be that § 67 (6) will lead to results unjust to employers in some cases, but if a causal connection between the injury and the employment beyond the requirement that the injury occur in the course of employment is to be mandated, it can only be done by the legislature.
Appellants also contend that the lower court erred in holding that there was legally sufficient evidence that the infant claimant was wholly dependent upon the deceased employee at the time of her death, within the meaning of § 36 (8) (a) of Art. 101. We have carefully reviewed the record in *431 light of the controlling case authority 4 and find no error in the lower court’s affirmance of the Commission’s order finding that Dionne was totally dependent upon Brenda.
Judgment affirmed; costs to be paid by appellants.
Notes
. We granted certiorari prior to decision by the Court of Special Appeals.
. Section 67 (6) provides in pertinent part:
“ ‘Injury,’ ‘personal injury,’ ‘accidental injury’ and ‘accidental personal injury’ means only accidental injuries arising out of and in the eourse of employment... and includes an injury caused by the wilful or negligent act of a third person directed against an employee in the course of his employment.”
Section 67 (6) must be read in conjunction with the general coverage provisions of § 15 of the Act which require an employer to pay compensation *424 “for the disability or death of his employee resulting from an accidental personal injury sustained by the employee arising out of and in the course of his employment____”
. Maryland’s statute covering an award of compensation on behalf of an employee injured in the course of employment as a result of a wilful or negligent act of a third party is unique. In most jurisdictions, the infliction of such injuries must, in addition to occurring in the course of employment, *426 arise out of or because of the employment. Generally, injuries sustained by an employee as the result of an assault on his person by a third person are compensable if the injury can be attributed to a cause set in motion by the nature of the employment, or some condition or obligation having to do with the employment. See 1 A. Larson, The Law of Workmen’s Compensation § 11.00 etseq. (1978); 6 W. Schneider, Workmen’s Compensation Law % 1560 (3rd ed. 1948).
.
See
Bituminous Constr. Co. v. Lewis,
