Once again, excepting cases of impeachment, Congress only has investigatory powers for matters of a strictly legislative nature.

However, this will establish precedent that should the Resident be impeached, then taxes are fair game... including all of the fraud committed in his tax filings and shady foreign scheming. Of course, without the Senate, there won't be any successful impeachment, and it's not like you can even impeach an unlawful occupant of the office anyway.

Real tribunals. Real arrests. Real action. No more bullshitting.