In a number of cases in the State courts, interesting points have been raised and decided with reference to the obligation imposed by federal laws to affix stamps to certain documents. There is little doubt that the United States may in its own courts, or in other ways refuse to recognize the validity of unstamped documents, but it would seem that it may not dictate to state agencies what instruments they shall accept as valid and enforceable. Though Congress may provide that certain instruments shall be stamped and that if not so stamped they shall not be received as evidence in federal courts, the State cannot be compelled to exclude them as evidence in its courts upon that ground.

Three justices dissented from the judgment rendered in South Carolina v. United States. After a review of authorities, which in their judgment did not warrant the position assumed by the majority in the case on trial, these justices say, in answer to the contention that if the instrumentalities of the State in the control of the liquor trade be declared exempt from federal taxation, the way is opened to the States seriously to interfere with federal revenues by extending their operations in other similar directions: "But these extreme illustrations amount simply to saying that it is possible for the imagination to foreshadow conditions which, did they arise, would impair the government created by the Constitution, and, because such conjectures may be indulged in, the limitations created by the Constitution for the purpose of preserving both the state and national governments are to be disregarded. In other words, that the government created by the Constitution must now be destroyed, because it is possible to suggest conditions which, if they arise, would, in future, produce a like result. But the weakness of the illustrations as applied to this case is apparent. They have no relation to this case, since it is not denied that, as to liquor, the State has absolute power, and may prohibit the sale of all liquor, and thus prevent the United States from deriving revenue from that source. Again, therefore, when the true relation of the argument, to the case in hand is seen, it reduces itself to a complete contradiction, viz., a State may, by prohibition, prevent the United States from reaping revenue from the liquor traffic, but any other state regulation by which such result is accomplished may be prevented by the United States, because thereby the State has done indirectly only that which the State had the lawful power directly to do."

As to the point that the State of South Carolina was deriving a revenue from the conduct of the liquor business, the dissenting justices point to the fact that in previous cases it had been expressly settled that the law establishing the State dispensaries had not been passed as a revenue, but as a purely police measure.

It has also been held by state courts that the United States may not impose a stamp tax upon judicial processes of state courts, or forbid the recording of unstamped mortgages, or tax the official bonds of state officers.60