Even Politifact... can't argue that strongly against it... see the second section below.
If a pardon was granted, what would happen to the special counsel investigation?
Gaming out what impact a pardon might have on an ongoing investigation -- in the current case, that of special counsel Robert Mueller -- depends on who and what the pardon covered.
If Trump pardoned someone who was the target of the investigation, he or she would be immunized from prosecution.
Case law indicates that "Mueller could not use the grand jury or other prosecutorial tools, such as search warrants, to investigate someone whom he cannot indict," said Ronald D. Rotunda, a law professor at Chapman University who was an investigator during Watergate and later an advisor to special prosecutor Kenneth Starr during the Clinton administration. "That would be a real abuse of the prosecutorial power."
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Can the president pardon himself?
Even legal experts who argue that a president can’t pardon himself tend to agree that no one really knows for sure.
Perhaps the strongest argument for saying a self-pardon would be allowed is that the Constitution doesn’t explicitly prohibit it.
But there are several more circumstantial arguments that, collectively, make a strong case that a self-pardon would be impermissible, experts said.
For starters, the Constitution uses the word "grant," which ordinarily means giving to someone else, said Harold H. Bruff, an emeritus University of Colorado law professor. Going back to its English monarchical origins, a pardon has long been conceived as an act of mercy. Neither of these suggest something that can be done to oneself.
In addition, Bruff said that when the Constitution was being written, "a background value everywhere in the air was that no one should be a judge in their own cause." This notion, sometimes referred to in Latin as "
nemo judex in causa sua," is a longstanding common-law principle, he said.
"People cannot prosecute, judge, or sit on juries in their own cases. Like a judge who would have to submit to the authority of another judge if he were being prosecuted, a president must seek a pardon from his successor,"
wrote Brian Kalt, a Michigan State University law professor who has studied pardons extensively.
http://www.politifact.com/truth-o-m.../4-questions-about-presidential-pardon-power/
