The system of separation of powers in the united states government divides the power between the branches of government so that no one branch becomes too powerful.

The constitution divided powers among branches of government so as to make sure that their power checks and balances, which is between the various branches and if they try to change the system or unbalance then the other branches could take over.
The three branches which include judicial and its work is to interpret the laws, the executive which enforces the laws and legislative which make the laws. The separation of powers assured of having distinct roles for every branch. The constitution divides its powers between the states and the federal government.