Opinion: When A Presidential Pardon Is Illegal

It is a logical entailment of that ruling that the pardon power cannot be subject to prior legal constraints or limits on its valid exercise. Thus, though President Trump has blatantly ignored the procedures established to examine the propriety and circumstances of its exercise (there is in the Justice Department a pardon attorney who, with a staff, documents the relevant grounds for granting a pardon and makes recommendations based on past practice regarding its exercise), his pardon, once granted, as in the case of Sheriff Joseph Arpaio, cannot be undone.

Read the full opinion here.