As a tool to obstruct justice, the presidential pardon power is highly overrated. The main advantage a president (or anyone else) has when he’s been involved in a criminal conspiracy is that the best witnesses against him are his co-conspirators, and they can’t tell what they know without implicating themselves. Because of this, it’s important that witnesses can rely on their Fifth Amendment protections against self-incrimination: “No person…shall be compelled in any criminal case to be a witness against himself.” The way that right is legally interpreted, anyone who has been pardoned for a crime can no longer incriminate themselves and therefore can no longer refuse to answer questions with impunity.
If President Trump were to preemptively pardon Michael Cohen for every possible crime he may have committed (in much the same way that President Gerald Ford retroactively pardoned Nixon for unspecified crimes), then Cohen would be compelled to answer all the special counsel’s questions or face fresh charges if he did not. Trump would have to issue pardon after pardon after pardon to keep witnesses quiet, and that would be such a blatant obstruction of justice that even the Republicans in Congress could not ignore it.
It might be more effective to dangle the promise of a pardon. Paul Manafort, for example, might be willing to go through two humiliating, expensive and doomed trials rather than cooperate with federal investigators just so long as he believes his convictions will be wiped away by presidential fiat at the end of the process. But that’s a big gamble and it’s doubtful that this hope alone explains Manafort’s behavior. It’s probably more important that he owes nearly $20 million to a Russian oligarch who is believed to have connections to the Russian mafia. He’d probably testify against Trump in a heartbeat if it didn’t require him to also testify against Kremlin allies and murderous gangsters.
And, what good would it really do for the president if he pardoned Manafort after his trials? Manafort would immediately lose his right against self-incrimination and would have to sing or face new charges. Trump is better off if people like Cohen, Manafort and Roger Stone are fighting charges than if they are free from them, but that assumes that they won’t cooperate.
As far as we know, none of those three are presently cooperating, although Cohen at least seems eager to take that step. Once any one of them goes over to Mueller’s team, the jig is effectively up, and that’s why we see desperation like this today:
The only way pardons can work is in tandem with the clock on the investigation running out. If there is no investigation left after Manafort’s trials conclude, then no one will call a pardoned Manafort in and force him to testify.
Trump needs the investigation to end and he needs it to end very soon.
It’s not clear why he would ask Jeff Sessions to take that step since Sessions has recused himself from all matters related to the Russia investigation. Trump should have addressed this request to Deputy Attorney General Rod Rosenstein, who actually has the power to fulfill it.
Either way, though, it’s an effort to obstruct justice. Telling a subordinate that they should end an investigation into your possible crimes is the most obvious and indisputable effort to obstruct justice that can be conceived. That’s why FBI Director James Comey refused Trump’s request that he stop the investigation of Michael Flynn and then made sure to memorialize the conversation.
In any case, Trump cannot pardon himself out of this jam. Even without taking into account the fact that the presidential pardon power does not extend to state-filed charges, it’s simply not possible to keep the truth from coming out by pardoning all your co-conspirators.
His only chance is to somehow force the end of the investigation. Obviously he realizes this now, but he hasn’t found a way to do it that doesn’t just bolster the case against him.