Rod Rosenstein
Rosenstein warns Congress its continued probes will interfere with the Special Counsel's investigation. Republican Senators appear to agree.

Further evidence that Rod Rosenstein's decision to appoint Special Counsel to supervise the Russiagate investigation is intended at least in part to take the heat out of the affair has been provided by a private briefing Rosenstein has given to the Senate about his decision, of which the New York Times has provided a detailed account.

It seems that over the course of this briefing Rosenstein made it very clear that for the Special Counsel to conduct the investigation properly the various Congressional committees which are conducting their own probes into Russiagate will need to rein their investigations and basically shut them down
Five different Senate and House committees — including both congressional intelligence committees — are running inquiries into the Russian meddling. But the special counsel, Robert S. Mueller III, who was appointed on Wednesday, is widely expected to ask Congress to scale back public hearings with witnesses who might be integral to his investigation.....

Mr. Rosenstein also affirmed that the Justice Department's inquiry was focused on possible crimes, meaning that potential subjects of investigation would almost certainly refuse to testify before Congress or withhold documents from lawmakers for fear of possible prosecution.
To be clear, this should not be taken to mean that the FBI's counter-espionage investigation is now a criminal probe, an unwarranted extrapolation from Rosenstein's words that some have made, and one which flatly contradicts what Rosenstein said in his statement announcing the Special Counsel's appointment. As I have repeatedly pointed out, so far no crime has been detected despite 8 months of investigations.

Rather the point Rosenstein is making is that as the Russiagate investigation is looking into the question of possible collusion between the Trump campaign and Russia, the possibility of criminal proceedings if evidence of such collusion is ever found must now exist, and in view of this continued investigations and public hearings by Congressional committees into Russiagate potentially meddle in future prosecutions.

This is something which ought to have been obvious from the moment claims of collusion between the Trump campaign and Russia were first made. That Rosenstein has finally pointed it out shows that he knows his job, and that he is finally taken steps to bring order to the chaos.

It also incidentally suggests that one reason why the Russiagate scandal has spiralled so far out of control is because during the transition between administrations - with Sally Yates actively colluding in the scandal and Jeff Sessions recusing himself from dealing with it - there was no one in the Justice Department to supervise Comey's investigation properly.

With Rosenstein appointed Deputy Attorney General there now is, and he is moving quickly to bring the investigation to order and under control. His decision to appoint Special Counsel is a case in point, and Newsweek hints that he may have actually taken the decision to do this before Comey was fired, and that the furore precipitated by Comey's decision was not the reason for his decision to do this
According to Democratic Senator Richard Durbin, Rosenstein didn't say exactly when or why he decided a special counsel was necessary. "Clearly it wasn't last night, it's been a matter of a few days." he said. The Illinois Democrat added that Rosenstein "kind of rejects the premise that he wasn't going to appoint one" until pushed to do so by the recent headlines.
As I have said previously, despite claims to the contrary Rosenstein's memo about Comey was shows quite clearly that Rosenstein doesn't see Comey as a fit person to lead the FBI.

It is difficult to avoid the impression that after having come to the Justice Department, and having seen the mess Comey and Sally Yates have created, Rosenstein decided that new management was needed. That was why he pressed for Comey's dismissal in his memo and brought Mueller in.

It is of course another matter that the President then catastrophically botched the manner of Comey's dismissal, creating a furore which has done huge and unnecessary damage.

For their part Republican Senators at least seem to be accepting the logic of all this, and seem to be agreeing that Congress now needs to rein in its various inquiries. Here is how the New York Times reports it
Congress needs "to be focused on what our role is," said Senator John Cornyn, Republican of Texas and a member of the Intelligence Committee. "We're not the F.B.I. We're not the Department of Justice. We're conducting oversight investigations and that's, I think, our appropriate role."

Senator Lindsey Graham, Republican of South Carolina and a member of the Judiciary Committee, said, "You've got a special counsel who has prosecutorial powers now, and I think we in Congress have to be very careful not to interfere. Public access to this is probably going to be very limited now. It's going to really limit what the public will know about this."

For Congress, the appointment of a special counsel means "you're pretty well knocked out of the game," Mr. Graham said. "And that's probably the way it should be."
And here is how Newsweek does
"I think the shot to the body is it's now considered a criminal investigation," Republican Senator Lindsey Graham, a former military prosecutor, said as he exited the closed-door briefing in the basement of the Capitol. And Graham said that could impede Congress's "ability to conduct investigations of all things Russia." For example, "I find it hard to subpoena records of somebody like [former National Security Adviser Michael] Flynn, who may be subject to a criminal investigation because he has a right not to incriminate himself," Graham explained. "As to Mr. [James] Comey, the former director of the FBI, coming before the committee, if I were Mr. Mueller, I would jealously guard the witness pool.
Hopefully this means we will have no more zany hearings - with grandstanding performances from people like Representative Adam Schiff - of the sort we have had to put up with up to now.

This is a blow to the Democrats and the media who have been driving the Russiagate scandal, and who may now find that the Congressional hearings they have been using to keep the scandal going now dry up. This is what the New York Times says
The abrupt shift in priorities poses a challenge for Democrats, who were almost united in their call for a special counsel, but now face losing access to their most potent political weapon: public hearings, where Americans could hear firsthand from officials with concerns about Mr. Trump's administration.....

Senator Ron Johnson, Republican of Wisconsin, said he believed it would be more difficult for lawmakers to get information now.

"I think Democrats probably should be asking themselves, sometimes you've got to be careful about what you ask for," he said. "Because when you get it, all of a sudden you can't get answers to things because now it's an active investigation." (bold italics added)
It seems that there is now a question mark about whether even Comey will be able to go before the Senate to answer its questions about whether Trump pressured him in relation to the Russiagate investigation. Here is the New York Times again
Mr. Mueller's new grip on the investigation also called into question whether Mr. Comey would accept any of the invitations issued by multiple congressional committees to testify next week about his firing. The testimony was widely anticipated as a chance for Mr. Comey to discuss a memo he wrote that said Mr. Trump asked him in February to drop the investigation of Mr. Flynn, an assertion Mr. Trump emphatically denied on Thursday.
As I have said previously, Rosenstein's decision to appoint a Special Counsel - one it seems he may have made before Comey was dismissed - is indisputably the correct one. The Democrats were wrong to press for it - as Senator Ron Johnson says - whilst President Trump was wrong to resist it. The 'narrowing' or hopefully the silencing of the various Congressional hearings is the first beneficial result.

Unsurprisingly the New York Times reports that the Democrats left the briefing with Rosenstein extremely unhappy
Democrats appeared to share that concern as they trickled out of the roughly 90-minute briefing, describing Mr. Rosenstein's reticence to answer many questions. Several senators and aides said the meeting was contentious, and "most of the questions and indeed almost all the very challenging ones came from Democrats," said Senator Richard Blumenthal, Democrat of Connecticut.
To which all one can say is that as Senator Rod Johnson says one should be careful what one wishes for.