Sources close to Team Mueller discussed with me last week that it is expected Trump would refuse an interview AND that Mueller will then subpoena him. AND that our 3rd co-equal branch of government is appalled at the other two.
Don't forget, it's traditionally called "Roberts's Court" for a reason. The Chief Justice takes the SCOTUS legacy as an institution to heart. Not only am I told he has recused Gorsuch, but also that he reveres Obama. 
Sources have told me for months that not only has Chief Justice Roberts (and other justices) been tuned in to Trump/Russia investigation, but also that he is appalled at Congress' abdication of Checks & Balances on Trump.
The fight won't last near as long as NYTimes & MSM think. Remember, it was only 6 weeks between Nixon being wildly applauded at his SOTU to everyone in Congress abandoning him. Trump's last stand will be shorter.
