Robert Mueller proved Wednesday that he might just be the least cooperative friendly witness Congress has ever faced. During close to six hours of Mueller’s testimony before two committees, House Democrats learned the hard way that you can lead a special counsel to an impeachment hearing, but you can’t make him testify.

The man who had spent the past two years leading the investigation of Russia’s attack on the 2016 election, and Donald Trump’s apparent obstruction of justice, had promised—warned, really—that he would not go beyond the four corners of the 448-page report he’d delivered earlier this spring. He lived up to that promise.

“The report is my testimony,” he told both committees. He refused even to read aloud key portions of that report, preferring to have congressional representatives read it aloud themselves, and then confirming in monosyllabic answers whether those portions were accurate. CBS tallied 41 one-word answers in just the first half of the morning Judiciary Committee hearing; Mueller declined more broadly to discuss all manner of other related and unrelated topics.

The day’s most clarifying exchange came during the first five minutes of the hearing, when Judiciary Committee chair Jerrold Nadler ran through a rapid-fire series of questions aimed at undermining President Trump’s consistent mantra of “No collusion, no obstruction.”

As Nadler opened, “Director Mueller, the president has repeatedly claimed that your report found there was no obstruction and that it completely and totally exonerated him, but that is not what your report said, is it?”

“Correct. That is not what the report said,” the former special counsel replied.

Then Nadler proceeded: “The report did not conclude that he did not commit obstruction of justice, is that correct?”

“That is correct,” Mueller said.

Nadler: “And what about total exoneration? Did you actually totally exonerate the president?”

Mueller: “No.”

Nadler: “Now, in fact, your report expressly states that it does not exonerate the president.”

Mueller: “It does.”

Nadler: “Your investigation actually found, ‘multiple acts by the president that were capable of exerting undue influence over law enforcement investigations, including the Russian interference and obstruction investigations.’ Is that correct?”

Mueller: “Correct.”

Even where Mueller could have said more, he chose not to do so.

Yet after that strong opening, Mueller’s reticence over the following hours made clear that he was not appearing on Capitol Hill to save American democracy. It’s clear Mueller feels like he’s contributed all he needs to the process. He’s done his work, delivering page after page of evidence and hard facts—not to mention three dozen criminal cases, indictments, and guilty pleas. Any further action or conclusions will have to come from the will of congressional Democrats.

While Democrats did manage to draw a troubling pattern of obstructive behavior by the president in the morning hearing, and in the afternoon expounded upon the Trump campaign’s gleeful willingness to accept Russian help in the 2016 election, the totality of the testimony managed to be both damning and underwhelming.

Mueller operated under tight constraints, some imposed by courts—which had issued gag orders in ongoing cases involving the Internet Research Agency and Trump associate Roger Stone—and some imposed by the Justice Department, in terms of avoiding discussions of internal deliberations or ongoing investigations. But even where Mueller could have said more, he chose not to do so. He specifically seemed to go through elaborate verbal gymnastics to avoid saying the word “impeachment.”

There was no bombshell moment, no snappy soundbite easily digestible in campaign ads or cable news, no crisp, succinct verbal indictment of the president’s behavior, nor memorable phrase to be recorded by history books. There was no harsh rebuke of Republican conspiracy theories, akin to a “Have you no sense of decency, sir?” moment, nor did Mueller clearly identify his own feelings about the president’s anti-American behavior. In fact, he seemed to go almost out of his way to avoid providing the soundbites Democrats wanted.