The best way to protect Hillary from criminal prosecution is to give every one in her inner circle immunity from prosecution allowing them to willfully lie and obstruct without fear of repercussions; they are immunized.
FBI Gave Immunity to 5 Clinton Aides Who Lied
This is how it works in a rigged system where law enforcement are obligated to the politicians that they were appointed/hired by. Americans were led to believe that the FBI was conducting and objective/impartial investigation of Hillary and friends which now turns out to have been another fabrication by the political Establishment to obstruct justice and allow Hillary to avoid prosecution;
FBI Director Let Hillary Off the Hook. Now, We Know Why He Wouldn't Talk About The Clinton Foundation.