What are checks and balances?
The principle of the separation of powers is that, in order to prevent oppressive government, the three powers of government should be held by separate bodies—the Legislature, Executive and Judiciary—which can act as checks and balances on each other.
Checks are mechanisms that limit or stop one person or arm of government from becoming too powerful and able to exceed their specific powers. Checks enable each arm of Government to review, criticise or override the actions of the other two arms.
In summary:
What would happen without checks and balances?