Within their jurisdiction, in the particular cases that come before them, and no more.
But they have no legislative or executive power, and no veto power. None whatsoever.
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The Executive not only dispenses the honors, but holds the sword of the community. The legislature not only commands the purse, but prescribes the rules by which the duties and rights of every citizen are to be regulated. The judiciary, on the contrary, has no influence over either the sword or the purse; no direction either of the strength or of the wealth of the society; and can take no active resolution whatever. It may truly be said to have neither FORCE nor WILL, but merely judgment; and must ultimately depend upon the aid of the executive arm even for the efficacy of its judgments."
-- Alexander Hamilton, Federalist 78, June 14, 1788
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Perhaps you might want to read Marbury in its entirety, rather than just the one sentence that modern leftists in the legal profession have turned on its head to make it say the exact opposite of what it actually meant.
Bump for later. So far this is a good read. Have to dig out my copies of “The Federalist Papers” and more importantly “The Antifederalist Papers”