What a government of limited powers needs, at the beginning and forever, is some means of satisfying the people that it has taken all steps humanly possible to stay within its powers. That is the condition of its legitimacy, and its legitimacy, in the long run, is the condition of its life. Our whole political system rests on the distinction between constitutional and other laws. The former are the solemn principles laid down by the people in its ultimate sovereignty; the latter are regulations made by its representatives within the limits of their authority, and the courts can hold unauthorized and void any act which exceeds those limits. The courts can do this because they are maintaining against the legislature the fundamental principles which the people themselves have determined to support, and they can do it only so long as the people feel that the constitution is something more sacred and enduring than ordinary laws, something that derives its force from a higher authority.
Consensus of the Governed: The Legitimacy of Constitutional Change,
64 Fordham L. Rev. 535
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