https://bensguide.gpo.gov/j-oath-office
At the start of each new Congress, in January of every odd-numbered year, the entire House of Representatives and one-third of the Senate takes an oath of office. For Members of the House, the Speaker will direct the Members to rise, and the oath is administered. A Senator-elect takes the oath of office from the presiding officer in an open session of the Senate. The current oath is as follows:
"I do solemnly swear (or affirm) that I will support and defend the Constitution of the United States against all enemies, foreign and domestic; that I will bear true faith and allegiance to the same; that I take this obligation freely, without any mental reservation or purpose of evasion; and that I will well and faithfully discharge the duties of the office on which I am about to enter: So help me God."
Needs repeating, often.
We could clear most of Congress out if that held any weight.
As it is, “We investigated ourselves and found we did nothing wrong...”