Seth B. Waxman, a partner at the Dickinson Wright law firm in Washington, served as a federal prosecutor in the United States Attorney's Office for the District of Columbia and has worked as a criminal defense lawyer in Washington and New York. The opinions expressed in this commentary are his own.



(CNN) Much is being made of the leaked topic areas relating to Robert Mueller's impending testimonial showdown with President Donald Trump. Having worked for 13 years as a federal prosecutor in the Clinton, Bush and Obama administrations, I can report that the reasons why the questions, crafted by the Trump legal team after consultation with the special counsel's office, were leaked are far more interesting than the leaked information itself.

First, the leaked information: In complex criminal cases, it is simply not unusual for prosecutors to disclose information or evidence to a target or subject of an investigation; it is called a "reverse proffer." Through such disclosures, prosecutors seek to advance the government's case. For example, oftentimes, prosecutors disclose specific incriminating evidence against a target or subject in an effort to flip that person against higher level members of a conspiracy. Prosecutors essentially lay out key evidence and say, "We got you; it's time to cut a deal."

In this case, Mueller's disclosure served a different prosecutorial purpose. By providing the general topic areas to the President's lawyers, Mueller short-circuited a lengthy court battle, which he would have ultimately lost, without giving away anything important about his investigation.

Months ago, Trump's lawyers likely informed Mueller that the President needed to consider whether to take legal action to restrict Mueller's questioning based on executive privilege, the Fifth Amendment, or other grounds. To do so, the President required an understanding of Mueller's topic areas.

While Mueller could have refused such a request, a federal judge would likely have required Mueller to disclose enough information for the President's lawyers to make those important legal determinations. It was entirely in Mueller's interest to voluntarily provide the information to avoid protracted litigation, which would have only delayed the opportunity to question the President.

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