"the senate shall have the sole power to try all impeachments. when sitting for that purpose, they shall be on oath or affirmation. when the president of the united states is tried, the chief justice shall preside: and no person shall be convicted without the concurrence of two thirds of the members present." —article i, section 3 because of the principle of the constitution states that congress can impeach a sitting president if he or she behaves in an unlawful manner.

With reference to Article I, Section 3; Because of the principle of checks and balances, the Constitution states that Congress can impeach a sitting President if he or she behaves in an unlawful manner. Article I, Section 3 grants congress their powers and limitations.

Checks and Balances should be in the blank.

“i think it is very plausible that if there are five votes to end the death penalty, it could be with the people who are on the court right now,” - smith

so basically it is not clearly and consistently imposed