At the time of the Constitutional Convention, the phrase—borrowed from British legal practice and the ongoing impeachment proceedings against the former British governor of India, Warren Hastings—was intended to address the problem of when an executive exercises legitimate authority but does so in a manner, as Alexander Hamilton put it, in “violation of some public trust.” A president, for example, has virtual plenary power to grant pardons, but if he exercises that authority so as to hide a crime, at a minimum he has violated his duty to faithfully (that is, in good faith) execute the laws.
Again, at the time of the Convention, a key problem the Framers wanted to address was the absence of an independent executive under the Articles of Confederation. They succeeded in establishing an office that could act with energy, decision, dispatch, and, if necessary, secrecy. The circle they had to square was providing for removal in the case where a president abused his broad discretion, without giving Congress the power to control presidential behavior by making removal from office too easy. Poor policy choices, ineffective administration, boorish behavior would be too low a bar for such removal. But an abuse of office—either obvious in the case of treason or bribery or less so in instances in which a president breaks the constitutional norms he is sworn to uphold—had to be on the docket if the newly crafted and powerful chief executive was to gain popular acceptance and the office not be amended by the state ratifying conventions.
Obviously, in comparison with treason and bribery, deciding whether a president has committed a high crime and misdemeanor will always be more of a judgment call. Hence, those calling for impeachment on these grounds will not readily escape the charge they are acting politically. Indeed, because impeachment only requires a simple majority vote in the House, it appears that the Constitution makes it relatively easy to impeach. However, the Constitution likewise makes it difficult to remove a president from office, requiring a two-thirds majority in the Senate for a conviction.
In sum, the Constitution’s structure frames the question of impeachment and removal around its textual insistence that with great executive power comes great responsibility. And because the Constitution seems to have created a relatively open door when it comes impeachment, a plausible assumption is that impeachment, qua impeachment, was never meant to be such an exceptional oversight mechanism. Just as it is plausible to argue that removal would be rare.
There is no question that a more routine use of impeachment inquiries might be disruptive to the presidency. On the other hand, the threat of it being employed more often might just put some ballast back into our constitutional system in the face of the expansive sway of the modern presidency. It might temper just a bit presidents who think that, once popularly elected, they have a mandate to govern as they wish and ignore the constitutional fact that they have both powers and duties