This court follows the established construction of the statutes of a State by its Supreme Court. Such a construction is considered as a part of the statute, and we follow it to avoid two rules of property in the same State. But we do not follow the decisions of the Supreme Court of a State beyond a statutory construction as a rule of decision for this court. State decisions are always viewed with respect and treated as authority; but we follow the settled construction of the statutes, not because it is of binding authority, but in pursuance of a rule of judicial policy. But there is no pretence that the case of Dred Scott _v._ Emerson turned upon the construction of a Missouri statute; nor was there any established rule of property which could have rightfully influenced the decision. On the contrary, the decision overruled the settled law for near thirty years. This is said by my brethren to be a Missouri question; but there is nothing which gives it this character, except that it involves the right to persons claimed as slaves who reside in Missouri, and the decision was made by the Supreme Court of that State. It involves a right claimed under an act of Congress and the Constitution of Illinois, and which cannot be decided without the consideration and construction of those laws. But the Supreme Court of Missouri held, in this case, that it will not regard either of those laws, without which there was no case before it; and Dred Scott, having been a slave, remains a slave. In this respect it is admitted this is a Missouri question--a case which has but one side, if the act of Congress and the Constitution of Illinois are not recognised. And does such a case constitute a rule of decision for this court--a case to be followed by this court? The course of decision so long and so uniformly maintained established a comity or law between Missouri and the free States and Territories where slavery was prohibited, which must be somewhat regarded in this case. Rights sanctioned for twenty-eight years ought not and cannot be repudiated, with any semblance of justice, by one or two decisions, influenced, as declared, by a determination to counteract the excitement against slavery in the free States.