I looked this up to see what President Trump is up against. This is a tough situation, and anything goes. In this lawfare case to inflict financial damage on President Trump, there is no jury, the judge is the finder of fact and makes the rulings based on his own findings. Looking at several articles, I found an article that said : "A judge who makes an error of law will have their findings overturned on appeal. It is extremely difficult to overturn a finding of facts." The appeals court gives deference to the trial judge if they are the finder of fact. But if there is no info in the court record from which a reasonable judge could have reached that decision, then it can be appealed.