The thing that commentators do not seem to mention that in the American legal system, financial documents are not super-secret confidential. In my own legal work, I always request the tax returns and other financial records from the people and businesses on the other side of my cases. And, unless the case settles, I generally get the documents. No subpoena required. I'm talking about run-of-the-mill discovery. Every once in a while, someone resists, so I file a Motion to Compel and get a Court Order requiring that someone to turn over the records. But most of the time all it takes is asking because the other side knows if they refuse I can easily get a Court order. These records are not privileged. There is no legal basis for keeping them secret, even if my lawsuit was motivated by partisanship.