I believe how it works is that if the letter is not responded to, it becomes a subpoena. If that's not responded to, it becomes either criminal or civil contemp

I believe how it works is that if the letter is not responded to, it becomes a subpoena. If that's not responded to, it becomes either criminal or civil contempt of Congress. Bear in mind that this senator is chairman of the Senate Finance Committee. https://legalclarity.org/what-is-the-penalty-for-refusing-a-congressional-subpoena/ https://legalclarity.org/what-is-the-penalty-for-refusing-a-... https://www.senate.gov/about/powers-procedures/investigations.htm https://www.senate.gov/about/powers-procedures/investigation...