Alan Dershowitz says no:
The president can, as a matter of constitutional law, direct the attorney general, and his subordinate, the director of the FBI, tell them what to do, whom to prosecute and whom not to prosecute. Indeed, the president has the constitutional authority to stop the investigation of any person by simply pardoning that person.
His argument is that the obstruction of justice statutes can’t apply to the president because the president possesses the constitutional authority to stop an investigation—by issuing an order to the attorney general or FBI director, by firing them if they do not obey the order, or by pardoning the person under investigation. Any interpretation of the obstruction of justice statute that blocked this authority would violate the Constitution. (Dershowitz agrees that Congress can impeach the president for obstruction of justice but only because impeachment is a political process; on this, see below.)
This argument is superficially appealing but I don’t think it’s right. To see why, imagine that Congress passes a statute that says (for example): “the president may not order the FBI director to stop an investigation of the president or any other executive branch official.” If Dershowitz is right, this statute would violate the Constitution and be struck down by a court.
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