The significance of Trump’s pledge, if he is elected, to appoint a special prosecutor to investigate charges against Hillary:
According to Time Magazine,US federal law implies that independent counsel can be appointed if the attorney general determines that an investigation by the Department of Justice “would present a conflict of interest for the department or other extraordinary circumstances” and “that under the circumstances, it would be in the public interest to appoint …an outside special counsel,” .
The norm in a country governed by the Rule of Law is that the policing and prosecuting agencies independently decide whether to charge and prosecute – not politicians.
As the above passage says, appointing a special prosecutor- independent of the Department of Justice and the FBI – should occur only in extraordinary circumstances, such as when a conflict of interest occurs with respect to DOJ/FBI’s accountability. .
Such a conflict occurs where the prosecuting department is answerable to the person they would be asked to prosecute- e.g. White Water (Bill Clinton) or Watergate (Nixon).
Trump purports to say to can be used as an implement of power by the President where he does not like what the DOJ/FBI has already determined, where he believes they lack credibility.
Three dangers here:
1. The President could himself act in keeping with his own political interests
2. The President could take revenge on political opponents
3. ( the most alarming) The box would be open, the precedent set for future politics – the loser might lose their liberty as well as the election, truly a chilling effect on the willingness of people to become candidates.
Mr. Trump’s proposal is a paradigm shift into a potentially autocratic society