The DOJ could get a Grand Jury to indict Thomas for violation of 28 U.S.C. § 455. If they found him guilty (which is pretty obvious), there is no penalty specified for violating the law. But Article III, Section 1 says:

Quote
The judicial Power of the United States, shall be vested in one supreme Court, and in such inferior Courts as the Congress may from time to time ordain and establish. The Judges, both of the supreme and inferior Courts, shall hold their Offices during good Behaviour, and shall, at stated Times, receive for their Services, a Compensation, which shall not be diminished during their Continuance in Office.

I suspect a case could be made that willfully violating the constitution for corrupt reasons, is NOT "good Behavior".

Educating anyone benefits everyone.