In united states v. nixon, the supreme court’s ruling made it clear that
the executive branch is the most powerful branch, but the president must still obey the law.
impeachment is not desirable and is an option only in the most extreme cases.
the executive branch should not have more power than other branches of government.
impeachment may be used to remove a president from office, but only with congressional approval.

In the United States v. Nixon case, the Supreme Court ordered Nixon to deliver the unedited tape recordings and documents related to the Watergate Scandal, an event in which he was involved. However, the President refused to do so, claiming his "Executive Privilege", that is to say, his right as President to withhold information from other government branches to preserve confidential communications within the executive branch or to secure the national interest.

Nevertheless, the Court stated that the executive privilege had limits and it wasn't immune from judicial review, regarding the demands of due process of law, and he ought to show the evidence.

The Senate was the most powerful branch of the Roman republic, and senators held the position for life. The executive branch was made up of two consuls, elected yearly. These two consuls had almost kingly powers, and each could veto, or disapprove of the other's decision.

Explanation:

sorry I just only know about executive branch in roman republic