The reason we<span>
</span>have this form of government goes back to something called checks and balances.
Checks and balances in our government are very important and regulate power. Our government was designed so that not just one branch was to receive all the power in our federal government.
I'll give you an example:
Say the Legislative branch (Congress) made a bill that said, "Anyone named John cannot say anything that dishonors the government." This is where the President (Executive branch) can come in and either veto or sign this bill. If he vetoes, then Congress can go back and revote. If he signs it, then this bill becomes federal law.
All is going dandy, and then the Supreme Court (Judicial) comes in and says, "I don't think that this is a Constitutional law." After review (it is called Judicial Review) they come to the consensus that this law violates the 1st Amendment. After they vote, they determine that this law is unconstitutional, and basically kill that law.
