SCOTUS just granted cert to Trump's challenge of the House's subpoenas to produce his financial records. Whether SCOTUS eventually rules for or against him, just that they granted certiorari means the President is entitled to judicial review of his opposition of Congressional committee subpoenas.
The 2nd article of impeachment alleges the President "obstructed Congress" by refusing to immediately comply with House subpoenas for certain persons to testify and instead put it to the Supreme Court whether he had to comply (nevermind that Obama also refused to allow certain persons to testify, and never even sought to make sure he was in the right). But that's dead in the water now. SCOTUS says the President can validly dispute Congressional subpoenas. Trump might lose, Trump might win ... but the point is there's nothing wrong with the President referring the matter for resolution to the Courts.
This is what Turley was talking about here:
SCOTUS hearing those cases in my understanding are because of a variety of different reasons due to each case having a different set of arguments for seeking the information and the white-house refusing while seeking an appeal to a higher court. Not all of the are congress seeking information. One in particular involves a criminal trial in Southern district of NY. I believe they are grouping them together.
These are subpoenas for private financial information (federal or business tax records).
I argue that this isn't the same as refusing subpoenas of government officials and government documents from a formal impeachment inquiry that have direct knowledge of matters involving the inquiry. Precedent of past court decisions speak to support the house in this area.
I'll do some more reading on each case as I haven't dissected them in detail, only been following the occasional news report as I knew they were going to be appealed to supreme court eventually.