es to act in the return of
fugitive slaves was challenged; and in Kentucky _v._ Dennison,[118]
decided on the eve of the Civil War, similar objection was leveled
against the provision of the same act which made it "the duty" of the
Chief Executive of a State to render up a fugitive from justice upon the
demand of the Chief Executive of the State from which the fugitive had
fled. The Court sustained both provisions, but upon the theory that the
cooperation of the State authorities was purely voluntary. In the Prigg
Case the Court, speaking by Justice Story, said: "* * * state
magistrates may, if they choose, exercise the authority, [conferred by
the act] unless prohibited by state legislation."[119] In the Dennison
Case, "the duty" of State executives in the rendition of fugitives from
justice was construed to be declaratory of a "moral duty." Said Chief
Justice Taney for the Court: "The act does not provide any means to
compel the execution of this duty, nor inflict any punishment for
neglect or refusal on the part of the Executive of the State; nor is
there any clause or provision in the Constitution which arms the
Government of the United States with this power. Indeed, such a power
would place every State under the control and dominion of the General
Government, even in the administration of its internal concerns and
reserved rights. And we think it clear, that the Federal Government,
under the Constitution, has no power to impose on a State officer, as
such, any duty whatever, and compel him to perform it; for if it
possessed this power, it might overload the officer with duties which
would fill up all his time, and disable him from performing his
obligations to the State, and might impose on him duties of a character
incompatible with the rank and dignity to which he was elevated by the
State. It is true," the Chief Justice conceded, "that in the early days
of the Government, Congress relied with confidence upon the co-operation
and support of the States, when exercising the legitimate powers of the
General Government, and were accustomed to receive it, [but this, he
explained, was] upon principles of comity, and from a sense of mutual
and common interest, where no such duty was imposed by the
Constitution."[120]

Eighteen years later, in Ex parte Siebold[121] the Court sustained the
right of Congress, under article I, section 4, paragraph 1 of the
Constitution, to impose duties upon State election officials in
co