delivered the opinion of the court.
This writ of error brings up for review a judgment of the Supreme Court of Pennsylvania, sustaining the validity of'a statute of that Commonwealth, relating to the manufacture md sale of what is commonly called oleomargarine butter.
. at judgment, the plaintiff in error contends, denies to him certain rights and privileges specially claimed under the Fourteenth Amendment to the. Constitution of the United States. ■
By acts of the General Assembly of Pennsylvania, one approved May 22, 1878, and entitled “An act to prevent deception in the sale of butter and cheese,” and the other approved May 24, 1888, and entitled “An act for the protection of dairymen, and to prevent deception in sales of butter' and cheese,” provision was made for the stamping, branding, or marking, in a prescribed mode, manufactured articles or substances in semblance or imitation of butter or cheese, not the legitimate product of the dairy, and not made exclusively of milk or cream, but into which oil, lard, or fat, not produced from milk or cream, entered as a component part, or into which melted butter or any oil thereof had been introduced to -take the place of cream. Laws of Pennsylvania, 1878, p. 87; 1883, p. 43.
But this legislation, we presume, failed to accomplish the objects intended by the legislature. For, by a subsequent act, approved May 21, 1885, and which took effect July 1, 1885, •entitled “ An act for the protection of the public health and to prevent adulteration of dairy products and fraud in the sale thereof,” Laws of Pennsylvania, 1885, p. 22, No. 25, it was provided, among other things, as follows :
“ Section 1. That no person, firm, or corporate body shall manufacture out of any oleaginous substance or any compound ■of the same, other than that produced from unadulterated milk or of cream from the same, any article designed to take •the place of butter or cheese produced from pure unadulterated milk or cream from the same, or of any imitation or adulterated butter or cheese, nor shall sell or offer for sale, or have in his, her, or their possession, with intent to sell the same, as an article of food.
*680“ Section - 2. Every sale of such article or substance, which is prohibited by the first section of this act, made after this act shall take effect, is hereby declared to be unlawful and void, and no action shall be. maintained in any of the courts in this State to recover upon any contract for the sale of any such article or substance.
“ Section 3.' Every person, company, firm, or corporate body who shall manufacture, sell, or offer or expose for sale or have in his, her, or their possession with intent to sell, any substance, the manufacture and sale of which is prohibited by the first section of this act, shall, for every such offence, forfeit and pay the sum of one hundred dollars, which shall- be recoverable with costs by any person suing in the name of the Commonwealth as debts of like amounts are by law recoverable ; one-half of which sum, when so recovered, shall be paid to the proper county treasurer for the use of the county in which suit is brought and the other half to the person or persons at whose instance such a suit shall or may be commenced and prosecuted to recovery.
“ Section 4. Every person who violates the provisions of the first section of this act, shall be deemed guilty of a misdemeanor, and upon conviction shall be punished by a fine of not less than one hundred ■ dollars, nor more than three hundred, or by imprisonment in the county jail for not less than ten nor more- than thirty days, or both such fine and imprisonment for the first offence, and imprisonment for one year for every subsequent offence.”
The plaintiff in error was indicted, under the last statute, in the Court of Quarter Sessions of the Peace in Dauphin County, Pennsylvania. The charge in the first count of the indictment is, that he unlawfully sold, “ as an article of food, two cases, containing five pounds each, of an article designed to take the place of butter produced from pure, unadulterated milk or cream from milk, the said article so sold, as aforesaid, being an article manufactured out of certain oleaginous substances and compounds of the same other than that produced from unadulterated milk or cream from milk, and said article so sold, as aforesaid, being an imitation butter.” In the *681second count the charge is that he unlawfully had in his possession, “ with intent to sell the same, as an article of food, 'a quantity, viz., one hundred pounds, of imitation butter, designed to take the place of butter produced from pure, unadulterated milk or cream from the same, manufactured out of certain oleaginous substances, or compounds of the same other than that produced from milk or cream from the same.” ■
It was agreed, for the purposes of the trial, that the defend-1 ant, on July 10, 1885,.in the city of Harrisburg, sold to the prosecuting witness, as an article of food, two original packages of the kind described in the first count; that such packages were sold and bought as butterine, and not as butter produced from pure, unadulterated milk or cream from unadulterated milk ; and that each of said packages was, at the time of sale, marked with the words, “Oleomargarine Butter,” upon the lid and side in a straight line, in Homan letters half an inch long.
It was also agreed that the defendant had in his possession one hundred pounds of the same article, with intent to sell it as an article of food.
This was the case made by the Commonwealth.
The defendant then offered to prove by Prof. Hugo Blanck that he saw manufactured the article sold to the prosecuting witness; that it was made from pure animal fats; that the process of manufacture was clean and wholesome, the article containing the same elements as dairy butter, the only difference between them being that the manufactured article contained a smaller proportion of the fatty substance known as butterine; that this butterine existed in dairy butter in the proportion of from three to seven per cent, and in the manufactured article in a smaller proportion, and was increased’ in the latter by the introduction' of milk and cream; that this having been done, the article contained all the elements of butter produced from pure unadulterated milk or cream from the same except that the percentage of butterine was slightly smaller; that the only effect of butterine was to give flavor to the butter and that it had nothing to do with its wholesomeness ; that the oleaginous substances in the manufactured art!*682cle were substantially identical with tbiose produced from milk or cream; and that the article sold to the prosecuting witness was a wholesome and nutritious article óf food, in all respects as wholesome as butter produced from pure unadulterated . milk or cream from unadulterated milk.
The defendant also offered to prove that he was engaged in the grocery and provision business in the city of Harrisburg, and that the article sold by him was part of a large •and valuable quantity manufactured prior to the 21st of May, Í885, in accordance with the laws of this Commonwealth relating to the manufacture and sale of said article, and so sold by him; that for the purpose of prosecuting that business large investments were made by him in the purchase of suitable real estate, in the erection of proper buildings, and in the purchase of the necessary machinery and ingredients; that in his traffic in said article he made large profits; and, if prevented from continuing it, the value of his property employed therein would be entirely lost, and he be deprived of the means of livelihood.
To each offer the Commonwealth objected upon the ground that the evidence proposed to be introduced was immaterial and irrelevant.
The. purpose of these offers of proof was avowed to be: (1) To show that the article sold was a new invention, not an .adulteration of dairy products, nor injurious to the public Health, but wholesome and nutritious as an article of food, ■and that its manufacture and sale were in conformity to the -acts of May 22, 1878, and May 24, 1883. (2) To show that the statute upon which the prosecution was founded, was unconstitutional, as not a lawful exercise of police power, and, also, because it deprived the defendant of the lawful use “ of his property, liberty, and faculties, and destroys his property without making compensation.”
The court sustained the objection to each offer, and excluded the evidence. An exception to that ruling was duly taken by the defendant.
A verdict of guilty having been returned, and motions in arrest of judgment and for a new trial Having been overruled, *683the defendant was adjudged to pay a fine of one hundred dollars and costs of prosecution, or give bail to pay the same in ten days, and be in custody until the judgment was performed. That judgment was affirmed by the Supreme Court of the State. 114 Penn. St. 265.
This case, in its important aspects, is governed by the principles announced in Mugler v. Kansas, 123 U. S. 623.
It is immaterial to inquire whether the acts with which the defendant is charged were authorized by the statute of May 22, 1878, or by that of May 24, 1883. The, present prosecution is founded upon the statute of May 21, 1885 ; and if that statute be not in conflict with the Constitution of the United States, the judgment of the Supreme Court of Pennsylvania must be affirmed.
It is contended that the last statute is void in that it deprives all coming within its provisions of rights of liberty and property without due process of law, and denies to them the equal protection of the laws; rights which are secured by the Fourteenth Amendment to the Constitution of the United States.
It is scarcely necessary to say that if this statute is a legitimate exercise of the police power of the State for the protection of the health of the people, and for the prevention of fraud, it is not inconsistent with that Amendment; for it is, the settled doctrine of this court that, as government is organized for the purpose, among others, of preserving the public health and the public morals, it cannot divest itself of the power to provide for those objects; and that the Fourteenth Amendment was not designed to interfere with the exercise of that power by the States. Mugler v. Kansas, 123 U. S. 663; Butchers’ Union Co. v. Crescent City Co., 111 U. S. 746, 751; Barbier v. Connolly, 113 U. S. 27 ; Yick Wo v. Hopkins, 118 U. S. 356.
The question, therefore, is whether the prohibition of the manufacture out of oleaginous substances, or out of any compound thereof other than that produced from unadulterated milk or cream from unadulterated milk, of an article designed to take the place of .butter or cheese produced from pure un*684adulterated milk or cream from unadulterated milk, or the prohibition upon the manufacture of any imitation or adulterated butter or cheese, or upon the selling or offering for sale, or having in possession with intent to sell, the same, as an article of food, is a lawful exercise by the State of the power to protect, by police regulations, the public health.
The main proposition advanced by the defendant is that his enjoyment upon terms of equality with all others in similar circumstances of. the privilege of pursuing an ordinary calling or trade, and of acquiring, holding, and selling - property, is an essential part of. his rights of liberty and property, as guaranteed by the Fourteenth Amendment. The court assents to this general proposition as embodying a sound principle of constitutional law. But it cannot adjudge that the defendant’s rights of liberty and property, as thus defined, have been infringed by the statute of Pennsylvania, without holding that, although it may have been enacted in good faith for the objects expressed in its title, namely, to protect the public health and to prevent the adulteration of dairy products and fraud in the sale thereof, it has, in fact, no real or substantial relation to those objects. Mugler v. Kansas, 123 U. S. 623, 661. The court is unable to affirm that this legislation has no real or substantial relation to such objects.
It will be observed that the offer in the court below was to show by proof that the particular articles the defendant sold, and those in his possession for sale, in violation of the statute, were, in fact, wholesome or nutritious articles of food. It is entirely consistent with that offer that many, indeed, that most kinds of oleomargarine butter in the market contain ingredients that are or may become injurious to health. The ■court cannot say, from anything of which it may take judicial cognizance, that such is not the fact. Under the circumstances disclosed in the record, and in obedience to settled rules of constitutional construction, it must be assumed that such is the fact. “Every possible presumption,” Chief Justice Waite said, speaking for the court in Sinking Fund Cases, 99 U. S. 700, 718, “is in favor of the validity of a statute, and this continues until the contrary is shown beyond a rational doubt. *685One -branch of the government cannot encroach on the-domain of another without danger. The safety of our institutions depends in no small degree on a strict observance of this salutary, rule.” See, also, Fletcher v. Peck, 6 Cranch, 87, 128; Dartmouth College v. Woodward, 4 Wheat. 518, 625 ; Livingston v. Darlington, 101 U. S. 407.
Whether the manufacture of oleomargarine, or imitation butter, of the kind, described in the statute, is, or may be, conducted in such a way, or with such skill, and secrecy, as to baffle ordinary inspection, or whether it involves such danger to the public health as to require, for the protection of the people, the entire suppression of the business, rather than its regulation in such manner as to permit the manufacture and sale of articles of that class that do not contain noxious ingredients, are questions of fact and of public policy which belong to the legislative department to determine. And as it dees not appear upon the face of the statute, or from any facts of which the court must take judicial cognizance, that it infringes-rights secured by the fundamental law, the legislative'determination of those questions is conclusive upon the courts. It is not a part of their functions to conduct investigations of facts entering into questions of public policy merely, and to sustain or frustrate the legislative will, embodied in statutes, as they may happen to approve or .disapprove its determination of such questions. The power which the legislature has to promote the general welfare is very great, and the discretion which that department of the government has, in the employment of means to that end, is very large. While both its power and its discretion must be so exercised as not to impair the fundamental rights of life,-liberty, and property:' and while, according to the principles upon which our institutions rest, “ the very idea that one man may be compelled to hold his life, or the means of living, or any material right essential to the enjoyment of life, at the mere will of another, seems to be intolerable in any country where freedom prevails, as being the essence of slavery itself; ” yet, “ in many cases of mere administration, the responsibility is purely political, no appeal lying except to the ultimate tribunal of the public judg*686ment, exercised either in- the pressure of public opinion or by 'means of the suffrage.” . Yick Wo. v. Hopkins, 118 U. S. 370. The case before us belongs to the latter class. The legislature of Pennsylvania, upon the fullest investigation, as we must conclusively presume, and upon reasonable grounds, as must be assumed from the record, has determined that the prohibition of the sale, or offering for sale, or having in possession to> sell, for purposes of food, of any article manufactured out of oleaginous substances or- compounds other than those produced from unadulterated milk or cream from unadulterated milk,, to take the place of butter produced from unadulterated milk or cream from unadulterated milk, will promote the public-health, and prevent frauds in the sale of such articles. If all that can be said of this legislation is that it is unwise, or unnecessarily oppressive to those manufacturing or selling wholesome oleomargarine, as an article of food, their appeal must be to the legislature, or to the ballot-box, not to the judiciary. The latter cannot interfere without usurping powers committed to another department of government.
It is argued, in behalf of the defendant, that if the statute-in question is sustained as a valid exercise of legislative power, then nothing stands in the way of the destruction by the-legislative department of the constitutional guarantees off liberty and property. But the possibility of the abuse off legislative power does not disprove its existence. That possibility exists even in reference to powers that are conceded to> exist. Besides, the judiciary department is bound not to give effect to statutory enactments that are plainly forbidden by the Constitution. This duty, th¿ court has said, is always one-of extreme delicacy; for, apart from the necessity of avoiding-conflicts between coordinate branches of the government,, whether state or national,-it is often difficult to determine whether such enactments are within the powers granted to or possessed by the legislature; Nevertheless, if the incompatibility of the Constitution and the statute is clear or palpable,, the courts must give effect to the former. And such would be-' the duty of the court if the state legislature, under the- pretence of .guarding the public health,- the public morals, or the.*687public safety, should invade the rights of life, liberty, or property, or other rights, secured by the supreme law of the land.
The objection that the statute is repugnant, to the clause of' the Fourteenth Amendment forbidding the denial by the State-to any person within its jurisdiction of the equal protection of the laws, is' untenable. The statute places under the samprestrictions, and subjects to like penalties and burdens, all who manufacture, or sell, or offer for sale, or keep in possession to sell, the articles embraced by its prohibitions; thus recognizing and preserving the principle of equality among those-engaged in the same business. Barbier v. Connolly, 113 U. S. 27; Soon Hing v. Crowley, 113 U. S. 703; Missouri Pacific Railway Co. v. Humes, 115 U. S. 512, 519.
It is also contended that the act of May 21, 1885, is in con-flict with the Fourteenth Amendment in that it deprives the-defendant of his property without that compensation required by law. This contention is without merit, as was held in Mugler v. Kansas.
Upon the whole case, We are of opinion that there is no error in the judgment, and it is, therefore,
Affirmed.