WASHINGTON — The lesson of this impeachment so far for President Donald Trump and his successors is that there are major strategic and tactical advantages to simply refusing to send witnesses and documents to Congress.
Not only has the president benefited from blocking the evidence itself, but his defenders have argued — compellingly in the minds of some observers — that the House Democrats' case against him on both articles of impeachment is weaker because they did not wait to see if courts would compel testimony and the production of documents at issue.
But it's not clear that the president, who has said repeatedly that Article II of the Constitution gives him the authority to do "whatever I want," would abide by either a Senate vote to subpoena witnesses (from another Article I branch) or a Supreme Court ruling requiring their participation (from the Article III branch).
The Senate could find out quickly with a vote to compel testimony from a single witness — or the production of a single document — whether Trump is so convinced of the supremacy of his office that he would defy Congress in the midst of a trial over whether his use of power is so abusive that it represents a threat to the checks and balances fundamental to the functioning of the republic.
By any account, Trump has taken an unusually broad view of executive power for a modern president. He issued a blanket order to administration officials to defy House subpoenas — though some ignored him — and his agencies refused to produce documents sought by investigators. But at that time, Trump was fighting a Democratic-led House, and he surely believed he could portray his recalcitrance as a matter of protecting himself from partisan warfare.
He has also shown a willingness to reject the authority granted to Congress when he has not been under threat of impeachment and removal from office, as he did when he chose to shift money appropriated by lawmakers for other purposes to build a border wall — a plan that is still caught up in the federal courts — and when he freeze the $391 million in aid that the House says was held back to extort Ukraine into tampering with the 2020 election.
In both cases, Republican and Democratic lawmakers used the spending power granted to them under the Constitution, and the president substituted his own judgment for theirs. Building a border wall was the most prominent promise of his 2016 campaign — one he hopes to be on the road to fulfilling for his 2020 re-election campaign — and House prosecutors say the aid for Ukraine was withheld to get officials in Kyiv to announce two probes important to his political fortunes: one into a main rival for the presidency, former Vice President Joe Biden, and one that would falsely suggest Russia did not try to assist him in his first election.
But in neither of those instances was Trump already impeached and awaiting a vote in the Senate on whether he should be removed from office because of his alleged ongoing abuse of power and obstruction of Congress.
The Senate could run a spot check on whether it has any institutional power in the Trump era, whether it will when he is no longer president and whether he sees any limits on his authority by ordering him to serve up witnesses and documents. Perhaps senators don't want the answers to those questions. Perhaps they already know them, instinctively.
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Trump has not approached the recalcitrance of President Andrew Jackson, who — in what is likely an apocryphal tale — is alleged to have responded to the news of an adverse ruling by Chief Justice John Marshall by saying, "Now let him enforce it."
But a call for witnesses and documents from the Senate would force Trump to choose between revelation and escalation. The stonewall playbook has worked for Trump so far, and any future president accused by the House of any criminal act or offense against the Constitution would surely follow it if the Senate chooses not to press the issue now.
If the Senate chooses to end its trial without pushing Trump for more information, not only it will be tolerating his expansive view of presidential authority; it will also be ceding more of its power to him, to his office and to his successors.