Which action of president franklin d. roosevelt challenged the principle of checks and balances?

theodore roosevelt 26th u.s. president : i admire his energy and passion. he was a fundamentally good man, brilliantly intelligent, possessed of extraordinary will and ability, supremely self-confident, bold, egalitarian, idealistic…. , lord, can we have him back?

a. by accepting the election of president abraham lincoln in 1860 and convincing other southern states to do the same