Which principle ensures that no single branch of government becomes too powerful?

The principle that ensures no single branch of government becomes too powerful is checks and balances. This framework is designed to maintain an equilibrium among the legislative, executive, and judicial branches, allowing each branch to monitor and limit the actions of the others. Each branch is given specific powers and responsibilities, but it also has the authority to restrict the powers of the other branches. For instance, while the legislature creates laws, the executive can veto them, and the judiciary can deem them unconstitutional. This interdependence helps prevent any one branch from accumulating excessive power and thus protects against tyranny.

While separation of powers is also a relevant concept, it specifically refers to the division of government responsibilities among the three branches, rather than the mechanisms by which those branches check each other's powers. Popular sovereignty refers to the principle that the authority of government comes from the consent of the governed, and federalism deals with the division of power between national and state governments. These principles, while important, do not specifically address the issue of power balance among the branches of government like checks and balances do.