For Democrats and Republicans alike, Robert Mueller proves a frustrating witness: Analysis

For members of Congress, former special counsel Robert Mueller’s hours of testimony on Capitol Hill Wednesday appeared designed to serve two objectives for the warring political factions in Washington.

For Democrats, Mueller was to be the face of the evidence amassed during a 22-month investigation into Russian interference in the 2016 election and the alleged efforts by President Trump to impede that probe.

To Republicans, he was to be a foil who could help them mount an assault on the investigation’s underpinnings and findings.

It appeared neither side left the morning’s House Judiciary Committee hearing fully satisfied with the outcome. Mueller offered very little to support either narrative, declining requests to read out loud from the 448-page report, impeding the flow of the session by asking dozens of times for panelists to repeat questions, or telling them simply, “I can’t get into that.”

For Democrats who thought Mueller may give a full-throated voice to the suggestion that President Trump worked to impede the investigation – the quiet attorney, whose answers were rarely longer than a few words. may have proven disappointing.

For Republicans who thought he may shed light on the origins of the Russia probe – a focus of their efforts to argue there were political motives lurking behind it – Mueller’s stone-faced refusals to engage may have proven equally frustrating.

In part, prospects that his appearance would yield compelling television moments were dashed by Mueller’s halting delivery. At least 38 times Mueller said he would prefer members simply "refer to the report," according to an ABC News count. And at least 21 times, Mueller asked members to repeat their question.

One of the few flashes of emotion from Mueller came when a Republican congressman began to assert that members of the special counsel’s team had political motives.

“Can I speak for a second to the hiring practices?” Mueller said, in one of the rare moments where his volume rose.

“We strove to hire those individuals that could do the job,” he said. “I've been in this business for almost 25 years, and in those 25 years, I have not had occasion once to ask somebody about their political affiliation. It is not done. What I care about is the capability of the individual to do the job and do the job quickly and seriously and with integrity.”

Democrats tried to score points with questions they knew would yield favorable answers. Rep. Zoe Lofgren, a California Democrat, asked Mueller if the investigation found the Russian government “perceived it would benefit from one of the candidates winning?”

That goal was a major finding of the report, and Mueller delivered the desired answer, although he affirmed it haltingly:

“Which candidate would that be?” she asked.

“Well, it would be Trimp. Um. Trump. The president,” he replied.

Republicans sought to paint the entire hearing as a predicate for Democrats to mount impeachment hearings. Rep. Mike Johnson, a Republican from Louisiana, tried to hammer home that point: "Your report does not recommend impeachment, does it?"

But again, Mueller did not engage.

"I'm not going to talk about recommendations," Mueller responded. "I'm not going to talk about that issue."

Mueller was equally muted when Republicans sought to engage him in discussion of the role of research by former British agent Christopher Steele, which had initially been prepared on behalf of a research firm hired by attorneys for the Democratic Party and the campaign of Trump’s opponent, Hillary Clinton. Instead, he told members that others – such as the Department of Justice’s inspector general, were looking at them. He did not.

“So you're not going to respond to any of the questions regarding Christopher Steele or your interviews with him?” asked Rep. William Gregory Steube, a Florida Republican.

“As I said at the outset this morning, that was one of the investigations that I could not speak to,” Mueller replied.

ABC News' Ben Siegel, Trish Turner and Allie Pecorin contributed to this story.