Legal experts are doubtful a letter sent to defense and prosecution attorneys in Donald Trump’s now-concluded New York criminal trial will ultimately turn his guilty verdict into a “mistrial.” Friday afternoon Judge Juan Merchan notified both parties of a comment posted to the New York Unified Court System’s Facebook page apparently one day before the jury handed the ex-president a guilty verdict. “My cousin is a juror and says Trump is getting convicted,” it begins, adding emojis here and at the end. “Thank you folks for all your hard work!!!!” Professor of law and MSNBC legal analyst Joyce V…