The principle of Checks and Balances looks to enable each government branch (executive, judicial, and legislative) to apply a certain extent of influence over the other branches.
It was fundamental that the framers added it to the Constitution, as these functions guarantee the separation of powers. This is a key element for any Federal government to keep balance and ensure no individual branch gets too powerful in comparison to the others.
For example, the Executive branch can veto bills from the Legislative branch, but the Legislative branch can override that veto.
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