What is the main reason for the system of checks and balances in the u. s. constitution? a) checks and balances, as outlined in the u. s. constitution, allows the president to declare war when necessary. b) checks and balances, as outlined in the u. s. constitution, makes sure the judicial branch controls the president. c) checks and balances, as outlined in the u. s. constitution, assures that no one branch of government gets too powerful. d) checks and balances, as outlined in the u. s. constitution, allows the legislative branch has control over the judicial branch.