University of Arizona Separation of Powers Political Science Discussion

Consider the following quote by the prominent policy scholar, Don Kettl:

When the nation’s founders wrote the Constitution in Philadelphia, they produced two great inventions: the separation of powers, which gave a substantial check on the executive branch to the courts; and federalism, which shared governmental power between the federal government and the states.

Analyze two cases (one separation of powers, one federalism) that highlight these “great inventions” of the Constitution in action. These can be recent cases or historical.