Just how far does executive privilege stretch? The Trump administration plans to test it until it shreds, apparently. After the House Judiciary Committee subpoenaed several people in Donald Trump’s inner circle, White House counsel Pat Cipollone informed chair Jerrold Nadler that the administration would invoke privilege to prevent at least some of their testimony. That applies to Corey Lewandowski too, Cipollone made clear — even though Lewandowski never worked in the Trump administration, and even though the testimony has to do with the transition:

Last night, White House counsel Pat Cipollone sent a letter to Rep. Jerry Nadler (D-N.Y.), the committee’s chairman, saying that Lewandowski has been “directed … not to discuss the substance of any conversations he had with the President or senior Presidential advisers about official government matters, unless the information is expressly contained in the Report.”

Cipollone added the even more dubious claim that conversations Lewandowski had with Trump during the transition, before he even became president, might be protected by presidential privilege. “Discussions during this period may relate to decisions the President-elect would be making once he assumed office,” Cipollone asserts. “Accordingly, Mr. Lewandowski’s responses to specific questions relating to this period may implicate deliberative process privilege and other Executive Branch confidentiality interests.”

Cipollone said he will send a White House lawyer to accompany Lewandowski, a private citizen, and “advise, as necessary, with regard to specific questions that implicate privileged matters.”

That got the reaction one would expect from Nadler, who called it “dangerous”:

“This is a shocking and dangerous assertion of executive privilege and absolute immunity,” Nadler said in a statement Monday night. “The President would have us believe that he can willfully engage in criminal activity and prevent witnesses from testifying before Congress — even if they did not actually work for him or his administration.”

“If he were to prevail in this cover-up while the Judiciary Committee is considering whether to recommend articles of impeachment, he would upend the separation of powers as envisioned by our founders,” he added.

Calling this a legal and political minefield might be an understatement. Executive privilege is more of a custom than a set of hard-and-fast rules, based on precedent and constitutional interpretation. It usually covers discussions between presidents and their formal advisers on matters that do not cross over into legitimate congressional authority. Usually, both sides of a dispute over executive privilege end up working out accommodations to keep the judiciary from setting new precedent that might hamper future leverage.

Until now, anyway. Neither side in this fight seems interested in accommodations and compromise, and adding Lewandowski to the exec-priv list will almost certainly be seen as an escalation — and it’s likely intended to be. Trump wants to shut down Nadler’s endless investigations and will play the executive privilege card for as long as it works.

This looks like one play too many. It might be a tougher call with Rob Porter and Rick Dearborn, both of whom worked in the White House strictly in positions without any congressional oversight at all, but Lewandowski is, strictly speaking, a civilian when it comes to privilege.  Traditionally, executive privilege has been extended to formal advisers to a president. Lewandowski might have been a friend, but he’s never been appointed to a post in the White House, nor did he serve any official role in the transition. Usually, one has to be in the executive branch to qualify for a claim of executive privilege. Just because a president chats up his bowling partner, for instance, doesn’t make his footwork eligible for a privilege claim.

As to the claim being “dangerous,” that’s overstated too. Nadler can challenge it in court, and in this case he can bet pretty safely that he’ll win. It might be “dangerous” if courts uphold Trump’s interpretation that privilege covers informal advisers from the period before a president takes office, but the chances that courts will agree with that interpretation are between slim and none. Presidents are entitled to conduct frank and honest discussions with advisers to set policy, but if they want that covered by privilege, then they’d better hire them first.

Still, as a short-term stall tactic, it will work. Even a losing court fight ties Nadler up for a long time, even if it might end up eroding the room future presidents have in negotiating with future Congresses. The real danger in this standoff is that it will impact the constitutional balance not between Congress and the White House, but that it will increase the authority of the judiciary to settle political questions. Neither side seems terribly concerned about that, unfortunately.