It is sad.
You can't arrest someone for violating their oath of office when they have never signed the affidavit they took it.
That leaves other options that will not be pretty. A political purge is what we need. And before anyone says "They have rights" let's understand that they have committed High crimes and misdemeanor's against the Constitution and the American people. If executing is to harsh then they can be stripped of their office, pension or retirement and imprisoned. Better yet give them a choice: The rest of their lives in prison or a short walk off a plank.