It is often said that our governmental system is one of checks and balances for the purpose of restraining the undue exercise of power by the government or its officers, the theory being that unlimited power is not vested in any department; and, to the degree previously set forth in this chapter, this statement is measurably true. Each department of government does, in a sense, serve the purpose of a check upon the others. While the legislative department cannot directly control the action of the executive or judiciary, it can, by virtue of its sole power to provide for the raising and expenditure of money, exercise a very potent influence with reference to executive and judicial action; and the judiciary department, by virtue of its authority in a proper case to pass upon the validity of the acts of the legislature or the executive, can restrain those departments within the scope of their proper functions. Again, the division of sovereignty between the federal and the state governments, so that the federal government has supreme power as to limited subjects of a federal nature, while the state governments have general power as to all matters not placed in the control of the federal government, makes each, to some extent, a check upon the other. But the theory of checks and balances must not be interpreted as meaning that either the state or federal government may interfere with the other in the proper discharge of the powers conferred upon it; nor with the well-established rule that in case of an apparent conflict of authority between a state and the federal government, the latter has the ultimate power to decide upon the extent of its own authority. This power is to be exercised, it is true, in accordance with the provisions and limitations of the constitution, but the necessity of providing some tribunal where such conflicts of authority may be authoritatively decided in accordance with the constitution and the law, and not by force or revolution, has dictated the wise provision that the federal judiciary is vested with this ultimate authority. (See above, § 19.) In other words, the checks which federal and state governments may exercise with reference to each other, and likewise those which are vested in the departments of government, are, after all, merely the checks which, by the constitution, are imposed on each; and the whole matter comes to this, that no government, or department of government, can constitutionally exceed the authority given to it, nor act otherwise than as authorized by the constitution.