"...interested combinations of a Majority against the rights of a Minority"

“...We must not shut our eyes to the nature of man, nor to the light of experience. Who would rely on a fair decision from three individuals if two had an interest in the case opposed to the rights of the third? Make the number as great as you please, the impartiality will not be increased, nor any further security against justice be obtained, than what may result from the greater difficulty of uniting the wills of a greater number.
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“In all Govts. there is a power which is capable of oppressive exercise. In Monarchies and Aristocracies oppression proceeds from a want of sympathy & responsibility in the Govt. towards the people. In popular Governments the danger lies in an undue sympathy among individuals composing a majority, and a want of responsibility in the majority to the minority. The characteristic excellence of the political System of the U. S. arises from a distribution and organization of its powers, which at the same time that they secure the dependence of the Govt. on the will of the nation, provides better guards than are found in any other popular Govt. against interested combinations of a Majority against the rights of a Minority.”
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- James Madison: Note to his Speech on the Right of Suffrage. [The Records of the Federal Convention of 1787, Farrand's Records, Volume 3, CCCXLII.]