What if the president gives an order to do something improper or illegal?
Let's start with Justice. Since Sessions recused himself from the Russia investigation, an order to fire Mueller, for now, would go to Deputy Attorney General Rod Rosenstein -- who has strongly indicated he would refuse. In June, members of the Senate Appropriations Committee got this commitment: "I am not going to follow any orders unless I believe those are lawful and appropriate orders. Special counsel Mueller may be fired only for good cause, and I am required to put that cause in writing."
Can Congress obtain similar pledges from other senior officials of the Justice Department who would be in the chain of command? During the Watergate scandal, Attorney General Elliot Richardson and his deputy, William Ruckelshaus, felt bound by the commitments they had given Congress not to fire special prosecutor Archibald Cox. A similar chain of obligation should be forged now, to circumscribe Trump's ability to sack Mueller.
Given the expectation that Rosenstein (and probably others) would quit rather than fire Mueller, the White House seems to be thinking about installing a new attorney general who wouldn't have the recusal problem and could be counted on to fire Trump's nemesis. Members of Congress are said to be gaming this option, thinking of ways to block a recess appointment or to extract a promise from any Sessions successor to leave Mueller alone. That's another good firewall.
The best way for members of Congress to affirm their oath to "support and defend" the Constitution in this moment of stress would be to enact legislation (with a veto-proof majority) that establishes Mueller as an independent special counsel for the length of his investigation, and requires him to send Congress a final report on his findings. That may sound unlikely, but the alternative could be disastrous.
If Mueller was protected by law, Trump could pardon whoever he liked, but we could still be confident that the truth would prevail. Officials shouldn't wait until the bomb detonates; they should take precautions now.
David Ignatius' email address is email@example.com.
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