Are you ready for tomorrow?

Mueller is.

Robert S. Mueller III’s longtime right-hand aide will appear beside him at the witness table during Wednesday’s hearing with the House Judiciary Committee to assist as needed as the former special counsel answers questions about his investigation, people familiar with the hearing said.

The Judiciary Committee signed off on the unusual arrangement after Mr. Mueller made a last-minute request that the aide, Aaron Zebley, be sworn in as a witness alongside him.

[...]

Mr. Zebley will not be under oath or theoretically allowed to answer lawmakers’ queries. But he can confer privately with Mr. Mueller, 74, if the former special counsel needs assistance or guidance about how to respond.

  NYT

There may actually be points that he's more familiar with than Mueller as well.

Why was it important to put Mueller's age in that paragraph?

It is not uncommon for government witnesses to bring aides along to congressional hearings for that purpose, though in almost all cases the aides sit behind, rather than next to, the witness. Mr. Mueller is being asked to account for two-years worth of investigative details uncovered by a large team of investigators and to do so while avoiding the disclosure of nonpublic information.

It was unclear if Mr. Mueller had made a similar request to the House Intelligence Committee, the panel holding the second of two highly anticipated hearings on Wednesday where Mr. Mueller is scheduled to testify.

Wouldn't it be odd if he didn't?

Mr. Zebley has worked closely with Mr. Mueller for years. He worked alongside Mr. Mueller during his 22-month investigation, served as his chief of staff when Mr. Mueller was F.B.I. director and followed him into private practice at the WilmerHale law firm.

Maybe he's Mueller's support animal.

He filled a similar role on the special counsel’s team, coordinating the team and serving as a go-between with the Justice Department.

Mr. Popkin identified Mr. Zebley as the investigation’s “deputy special counsel” and said he “had day-to-day oversight of the investigations conducted by the office.”

The two panels had previously expected to talk to Mr. Zebley and another former member of the special counsel’s team, James L. Quarles III, in private sessions after the public hearings. But those meetings were canceled after the Justice Department objected.

So what? They're not members of the Justice Department.

Representative Doug Collins of Georgia, the top Republican on the Judiciary Committee, said the last-minute addition of a witness could violate House rules. He called on Democrats to reject the request.

“If Democrats believe it is the special counsel’s responsibility to testify to his report, they have no ground for outsourcing that duty at the expense of our committee’s integrity,” he said.

What's the problem? Nothing. They just live to object to everything, and in general, to make life miserable.

...but hey, do what you want...you will anyway.

UPDATE:



Pretty sure Mueller knows that.  Barr knows it, too, so the question is.

..why did he write that letter?

DOJ obstructing justice

The Justice Department is seeking to discourage Robert S. Mueller III’s deputies [Aaron Zebley and James L. Quarles III] from testifying before Congress, potentially jeopardizing an agreement for two of the former prosecutors to answer lawmakers’ questions in private next week, according to two government officials familiar with the matter.

[...]

It is unclear what effect the Justice Department’s intervention will have on the men’s eventual appearances, but it raises the prospect that a deal lawmakers thought they had struck last month for testimony from Mr. Mueller, the former special counsel, and the two prosecutors could still unravel.

Both Mr. Zebley and Mr. Quarles have left the Justice Department and are now private citizens, meaning that the department most likely cannot actually block their testimony. But the department’s view — depending on how strongly it is expressed — could have a chilling effect on two longtime employees and give them cover to avoid testifying.

[...]

Democrats on the two House panels reached a deal late last month, after weeks of negotiations, for testimony from the prosecutors. Under the terms outlined by lawmakers and officials familiar with the discussions, Mr. Mueller agreed to testify publicly under subpoena on July 17 in back-to-back, time-limited hearings before the Judiciary and Intelligence Committees.

But Mr. Zebley and Mr. Quarles tentatively agreed to make limited appearances as well to answer questions from lawmakers from the two committees behind closed doors. Those private appearances are still in flux, the congressional official said, speaking on the condition of anonymity to talk about discussions that were intended to be private.

[...]

Mr. Zebley is considered Mr. Mueller’s closest associate. He served as his chief of staff when Mr. Mueller was F.B.I. director, and he functioned in a similar role in the special counsel’s office, coordinating the team working for Mr. Mueller and as a go-between with the Justice Department. He is intimately familiar with most aspects of the investigation, and in a private session could probably add details and context that Mr. Mueller would not in public.

[...]

Mr. Quarles was heavily involved in the team’s investigation into whether Mr. Trump’s attempts to impede investigators constituted obstruction of justice, and he was the lead intermediary with the White House.

[...]

In an interview with The Associated Press, Mr. Barr said that the Justice Department would support Mr. Mueller if he wanted to back out. And he said that the department would seek to block any attempt by House Democrats to subpoena members of Mr. Mueller’s prosecutorial team.

  NYT