The question is simply this: Can a negro, whose ancestors were imported into this country, and sold as slaves, become a member of the political community formed and brought into existence by the Constitution of the United States, and as such become entitled to all the rights, and privileges, and immunities, guarantied by that instrument to the citizen? One of which rights is the privilege of suing in a court of the United States in the cases specified in the constitution...

The words "people of the United States" and "citizens" are synonymous terms, and mean the same thing. They both describe the political body who, according to our republican institutions, form the sovereignty, and who hold the power and conduct the government through their representatives. They are what we familiarly call the "sovereign people," and every citizen is one of this people, and a constituent member of this sovereignty. The question before us is, whether the class of persons described in the plea in abatement compose a portion of this people, and are constituent members of this sovereignty? We think they are not, and that they are not included, and were not intended to be included, under the word "citizens" in the constitution, and can therefore claim none of the rights and privileges which that instrument provides for and secures to citizens of the United States. On the contrary, they were at that time considered as a subordinate and inferior class of beings, who had been subjugated by the dominant race, and, whether emancipated or not, yet remained subject to their authority, and had no rights or privileges but such as those who held the power and the government might choose to grant them.

It is not the province of the court to decide upon the justice or injustice, the policy or impolicy, of these laws. The decision of that question belonged to the political or law-making power; to those who formed the sovereignty and framed the constitution. The duty of the court is, to interpret the instrument they have framed, with the best lights we can obtain on the subject, and to administer it as we find it, according to its true intent and meaning when it was adopted.

In discussing this question, we must not confound the rights of citizenship which a State may confer within its own limits, and the rights of citizenship as a member of the Union. It does not by any means follow, because he has all the rights and privileges of a citizen of a State, that he must be a citizen of the United States. He may have all of the rights and privileges of the citizen of a State, and yet not be entitled to the rights and privileges of a citizen in any other State. For, previous to the adoption of the constitution of the United States, every State had the undoubted right to confer on whomsoever it pleased the character of citizen, and to endow him with all its rights. But this character of course was confirmed to the boundaries of the State, and gave him no rights or privileges in other States beyond those secured to him by the laws of nations and the comity of States. Nor have the several States surrendered the power of conferring these rights and privileges by adopting the constitution of the United States...

It is very clear, therefore, that no State can, by any act or law of its own, passed since the adoption of the constitution, introduce a new member into the political community created by the constitution of the United States. It cannot make him a member of this community by making him a member of its own. And for the same reason it cannot introduce any person, or description of persons, who were not intended to be embraced in this new political family, which the constitution brought into existence, but were intended to be excluded from it.

The question then arises, whether the provisions of the constitution, in relation to the personal rights and privileges to which the citizen of a State should be entitled, embraced the negro African race, at that time in this country, or who might afterwards be imported, who had then or should afterwards be made free in any State; and to put it in the power of a single State to make him a citizen of the United States, and endue him with the full rights of citizenship in every other State without their consent? Does the constitution of the United States act upon him whenever he shall be made free under the laws of a State, and raised there to the rank of a citizen, and immediately clothe him with all the privileges of a citizen in every other State, and in its own courts?

The court think the affirmative of these propositions cannot be maintained. And if it cannot, the plaintiff in error could not be a citizen of the State of Missouri, within the meaning of the constitution of the United States, and, consequently, was not entitled to sue in its courts.

It is true, every person, and every class and description of persons, who were at the time of the adoption of the constitution recognized as citizens in the several States, became also citizens of this new political body; but none other; it was formed by them, and for them and their posterity, but for no one else. And the personal rights and privileges guaranteed to citizens of this new sovereignty were intended to embrace those only who were then members of the several State communities, or who should afterwards by birthright or otherwise become members, according to the provisions of the constitution and the principles on which it was founded. It was the union of those who were at that time members of distinct and separate political communities into one political family, whose power, for certain specified purposes, was to extend over the whole territory of the United States. And it gave to each citizen rights and privileges outside of his State which he did not before possess, and placed him in every other State upon a perfect equality with its own citizens as to rights of person and rights of property; it made him a citizen of the United States...

In the opinion of the court, the legislation and histories of the times, and the language used in the declaration of independence, show, that neither the class of persons who had been imported as slaves, nor their descendants, whether they had become free or not, were then acknowledged as a part of the people, nor intended to be included in the general words used in that memorable instrument...

It is too clear for dispute, that the enslaved African race were not intended to be included, and formed no part of the people who framed and adopted this declaration; for if the language, as understood in that day, would embrace them, the conduct of the distinguished men who framed the declaration of independence would have been utterly and flagrantly inconsistent with the principles they asserted; and instead of the sympathy of mankind, to which they so confidently appealed, they would have deserved and received universal rebuke and reprobation...