The "Imperial Presidency"
United States v. Nixon (1974)
The Supreme Court has the final voice in determining constitutional questions; no person, not even the president of the United States, is completely above the law; and the president cannot use executive privilege as an excuse to withhold evidence.
Youngstown Sheet & Tube Co. v. Sawyer (1952)
Decision that the President needs legislative authority to seize property of steel mills, limiting the power of the President.