Barbara McQuade

Opinion contributor

The evidence of obstruction of justice comes pouring off the pages.

Special counsel Robert Mueller’s report on his investigation into links between the Trump campaign and Russian interference in the 2016 presidential election chronicles 10\ separate episodes of potential obstruction of justice over their own 181-page volume.

We all know about President Donald Trump’s firing of FBI Director James Comey after he asked Comey to drop the investigation into Michael Flynn, Trump’s former national security adviser. That incident is in the report. The report also describes Trump’s editing of a draft press release to remove damaging information about the June 2016 Trump Tower meeting with Russians to get dirt on Hillary Clinton.

But new episodes of obstruction appeared in the report as well. For instance, after Flynn had resigned for lying to Vice President Mike Pence about discussing sanctions with Russian Ambassador Sergei Kislyak, Trump communicated a request to deputy security adviser K.T. McFarland to draft a false witness statement — an internal email denying that it was the president who had directed Flynn to discuss sanctions with Kislyak.

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"McFarland declined because she did not know whether that was true, and a White House Counsel's Office attorney thought that the request would look like a quid pro quo for an ambassadorship she had been offered," the report says. "The evidence did not establish that Trump was asking her to lie," it adds, but it was “sufficiently irregular" that McFarland felt the need to draft an internal memorandum" documenting his request.

The report also discusses an episode in which Trump asked White House Counsel Don McGahn to lie. According to the report, Trump wanted McGahn to issue a statement falsely refuting media accounts that Trump had asked McGahn have the special counsel removed. Several more incidents of potential obstruction are also included in the report.

Obstruction can be hard to prove

But Trump was not charged with obstruction of justice, we now know, because Attorney General William Barr decided that the evidence was not sufficient.

Mueller himself refrained from making a decision, in part, because he believed that he could not indict a sitting president, and therefore, “fairness concerns" counseled against bringing charges against Trump because he could not avail himself of the normal adversary process for "public name-clearing before an impartial adjudicator” — a sp[edy public trial.

When a federal prosecutor makes a charging decision, he is deciding not just that probable cause of a crime exists. Instead, a federal prosecutor charges a crime only if he believes that the evidence is sufficient to obtain and sustain a conviction, which means proof beyond a reasonable doubt, the very highest standard in the legal system. Obstruction of justice can be a particularly difficult crime to prove. In addition to proving that the person engaged in conduct to interfere with an official proceeding, a prosecutor must establish that the person acted with a corrupt intent or “bad purpose.”

One way Mueller could have attempted to determine Trump’s intent was to interview him. While prosecutors rarely call targets of an investigation to testify before a grand jury, DOJ policy permits them to do so if their testimony is important to the investigation and cannot be obtained from other witnesses. Here, interviewing Trump would have shed light on whether he had the corrupt intent necessary for obstruction of justice. While Trump would have been entitled to invoke his Fifth Amendment rights against self-incrimination, he always insisted he wanted to talk to Mueller, seizing the best of both worlds by claiming to want to talk while never having to go through with it.

Barr usurped congressional role for himself

In his report, Mueller acknowledges that the case “presents difficult issues that would need to be resolved if we were making a traditional prosecutorial judgment.” If he believed the evidence was not sufficient to obtain and sustain a conviction, Mueller certainly could have proceeded as he did with the conspiracy issue and concluded that the investigation did not establish obstruction. But instead, Mueller said that while his report “does not conclude that the President committed a crime, it also does not exonerate him.”

The report contains no indication that Mueller expected Barr to swoop in and make the decision for him. Instead, it appears that Mueller was providing the proverbial road map for members of Congress to take up the matter of obstruction in impeachment proceedings if they so choose, taking steps to “preserve the evidence when memories were fresh and documentary materials were available.”

Of course, Congress may still use the Mueller report as a road map for impeachment. Or Congress may calculate that the political cost of impeachment is too great and the likelihood of conviction too slim to make proceedings worth undertaking. Barr’s decision will make it a much steeper climb to convince Congress and the public that obstruction occurred.

That would leave it to a future attorney general to decide whether to file charges when Trump is no longer president, and no longer has the shield of office to protect him. The five-year statute of limitations on obstruction of justice will not expire until at least January 2022.

Barbara McQuade, a former U.S. attorney for the Eastern District of Michigan, is a professor at the University of Michigan Law School. Follow her on Twitter: @barbmcquade