“ While it was asserted that the law of Congress was supreme, and that judges and courts in every state were bound thereby, and that therefore the statute granting immunity would probably operate in the state as well as in the Federal courts, yet still, and aside from that view, it was said that while there might be a bare possibility that a witness might be subjected to the criminal laws of some other sovereignty, it was not a real and probable danger, but was so improbable that it needed not to be taken into account. ”

“ We think not. Assuming for this purpose that if the statute failed to give sufficient immunity from prosecution or punishment, it would violate the 14th Amendment, and that an imprisonment by virtue of the statute would be depriving the witness of his liberty without due process of law, we come to an examination of the extent of the immunity in this case. ”

“ It is contended on the part of the plaintiff in error that the court below denied to him the protection of § 10 of the Bill of Rights of the Constitution of Kansas, and also denied to him the benefit of the provision of the 5th Amendment to the Constitution of the United States, that no person should be compelled, in any criminal case, to be a witness against himself, and also that he has been deprived of the benefit of the 14th Amendment. ”