Free Enterprise Fund v. PCAOB: Congress created the Public Company Accounting Oversight Board as a self-regulating board that oversaw accounting firms nationwide. Five members of the board were only removable for cause by the SEC, who in turn were only removable for cause by the President. - Rule: If an agency has broad discretionary power, then two-level for cause removal restrictions are unconstitutional. o Unclear whether it would apply where an agency has limited discretion.