The argument made by the former AG is ridiculous. If it were true that a statement by the president of support for a person under investigation, than not only would Obama be guilty, but Trump would be guilty ten-fold. How many times has he said that Michael Flynn was good guy who was treated unfairly? How many times has he stated there was no collusion? How many times has he called the Russia investigation a hoax? If that is not "signalling" the Justice Department as to how he wants the investigation to turn out?
We all know that if the FBI determined that Hillary should be indicted and Loretta Lynch refused to, that information would have been leaked, or Comey himself would have made a statement