The powers of the government and the rights and privileges of the citizen are regulated and plainly defined by the Constitution itself, and when a Territory becomes a part of the United States, the Federal Government enters into possession in the character impressed upon it by those who created it. It enters upon it with its powers over the citizen strictly defined and limited by the Constitution from which it derives its own existence, and by virtue of which alone it continues to exist as a government and sovereignty. It has no power of any kind beyond it, and it cannot when it enters a Territory of the United States put off its character, and assume discretionary or despotic powers which the Constitution has denied to it. It cannot create for itself a new character separate from the citizens of the United States, and the duties it owes to them under the provisions of the Constitution.

( Source:

John Taylor, Messages of the First Presidency 3:116-17