Although the Constitution explicitly makes the Federal Government supreme, the idea that the States remain in some sense sovereign or autonomous has retained its vitality throughout the country's history. Following the ratification of the Federal Bill of Rights, the U.S. Supreme Court confined its application to national governmental action, thus avoiding a challenge to States' bills of rights. However, the 14th amendment dramatically extended the scope of the Federal Bill of Rights and altered the relationship between the State and Federal Court systems. The tension between the two systems was addressed in the U.S. Supreme Court decision in Michigan v. Long, which held that States may develop an independent body of civil liberties law to the exclusion of Federal law and may apply it so long as no federally guaranteed rights are abridged. However, it also reminded the States that when they act like Federal courts and interpret Federal rights, they are subject to review. 42 footnotes.