Daniel Hemel and I argue that if Trump pardons family members and aides who committed crimes in connection with Russia, then Trump could be guilty of obstruction of justice. But if Trump is guilty of obstruction of justice, can’t he also pardon himself of the obstruction crime? Some legal scholars think that a president can self-pardon. Nixon apparently considered it at his lawyers’ suggestion. The argument, boiled down to its essentials, is that the Constitution doesn’t say he can’t.
I am skeptical, but even if the president can self-pardon, Trump faces a further problem that someone like Kurt Gödel would appreciate. The problem for Trump is that if he pardons himself, and our theory is correct, then the self-pardon is itself an obstruction of justice (an obstruction of the investigation and possible prosecution of Trump himself for pardoning his family members and aides). Trump would need to issue yet another self-pardon to relieve himself of criminal liability for the first self-pardon. He could do that, of course, but then there is a second- (or is it third-?) order crime—the obstruction of the investigation into whether Trump has committed a crime by pardoning himself.
Trump can continue self-pardoning himself at higher orders until the moment he leaves office. But the final self-pardon itself will be a potential crime like all the others, and there is nothing Trump can do about that. Whatever the case, he should be prepared to sign a lot of documents.