Final answer:
Each branch of government derives its legitimacy and power from the consent of the people. Its ability to exert authority, which governs specific actions, is reliant upon this legitimacy. The branches are interdependent, operating within a system of checks and balances to ensure the separation of powers.
Step-by-step explanation:
Each branch of government depends on the legitimacy granted to them by the people they govern, as well as the de jure and de facto rules of the country. This legitimacy allows them to exert authority and carry out actions without the threat of popular rebellion. For example, in a democratic state like the United States, the consent of the people is what legitimizes the government's actions. Authority can extend to certain actions such as the power to raise taxes or declare war.
Each branch of government is also dependent on the others, as in rule-of-law systems. For instance, the judicial branch depends on the other branches and the population's respect for the rule of law to carry out its decisions. The separation of powers prevents power aggregation in the hands of one part of government, but can also lead to policy-making difficulties or gridlock when there's a political conflict.
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