AMNA NAWAZ: Late last month, the Justice Department fired several officials involved in the January 6 criminal prosecution, while others have been demoted to low-level positions.

They're just the latest moves that some say are part of a retribution campaign against anyone who worked on the January 6 investigation.

White House correspondent Laura Barron-Lopez spoke with one of the prosecutors who led that case.

LAURA BARRON-LOPEZ: Greg Rosen is the former chief of the Justice Department's Capitol Siege Section, where he helped lead the largest federal criminal case in U.S. history after the violent January 6 attack on the U.S. Capitol.

Last month, he left the Justice Department in the wake of President Trump's decision to pardon or commute the sentences of more than 1,500 January 6 defendants.

Greg Rosen joins me now.

Greg, thank you so much for being here.

GREG ROSEN, Former Justice Department Official: Thanks for having me.

LAURA BARRON-LOPEZ: You were a long time assistant U.S. attorney at the Justice Department.

You served there during the first Trump administration.

Did the January 6 pardons play a role at all in your resignation?

GREG ROSEN: Watching a case like the prosecution of the riot at the U.S. Capitol in January 6, 2021, was a culmination of efforts over the course of four years.

And watching it end in the way it did, not just with the pardons, but with the firings and arguably the dismantling of certain aspects of the Department of Justice, was incredibly disheartening.

And so did it play a role?

Sure, it played a role.

LAURA BARRON-LOPEZ: As you mentioned, there were so many people that worked on those January 6 cases.

There were thousands that worked on it across federal law enforcement.

And many of them were either fired or have resigned since then.

What do you think this says about the future of the Justice Department or the way the Trump administration is handling the Justice Department?

GREG ROSEN: I mean, I hope it's just a blip on the long record of an esteemed Department of Justice.

I mean, the Justice Department is named for virtue.

It means something.

And to have individuals leave the Department of Justice because not only the priorities of the department have changed, which is totally permissible from one administration to the other, but to see it done in this fashion is incredibly, to say the least, disappointing.

LAURA BARRON-LOPEZ: I want to ask you about a recent Trump administration hire, Jared Wise.

He's a former FBI agent who participated in the January 6 attack on the Capitol.

He was charged by the Justice Department for encouraging the mob to kill police officers.

He was subsequently pardoned by President Trump.

But now he's an adviser to Trump's Justice Department working on what's called the Weaponization Working Group.

What kind of message does it send that this person who participated in the January 6 attack is now inside the Justice Department?

GREG ROSEN: Political views are now something that are subject to attack in our republic.

And part of America is having that ability to dissent, having that ability to sort of freely speak on these issues.

So I think it sends an incredibly dangerous message.

I think it's also incredibly hypocritical.

This administration has consistently talked about backing the blue and ensuring the protection of law enforcement.

So to hire somebody who was accused -- and, at the time, remember this was a public trial with public exhibits that was vetted by a federal judge -- at the time having an individual who is alleged to have said, "Kill him, kill him, kill him," and encouraged political violence against police officers, to hire that person to the department sends exactly the opposite message that I think the department was trying to convey.

LAURA BARRON-LOPEZ: This week, the Justice Department announced that it's investigating former FBI Director James Comey and former CIA Director John Brennan.

The president was asked if he wanted to see both of these men -- quote -- "behind bars."

And here's what he said: DONALD TRUMP, President of the United States: I will tell you, I think they're very dishonest people.

I think they're crooked as hell.

And maybe they have to pay a price for that.

I believe they are truly bad people and dishonest people.

So, whatever happens, happens.

LAURA BARRON-LOPEZ: What do you think these probes into Comey, into Brennan say about how the Justice Department's powers are being used against the president's perceived enemies?

GREG ROSEN: So, perception is reality.

And the perception right now is that, any time you do anything against the president or an ally of the president, that you will be subject to some sort of scrutiny or investigation simply for having the audacity to speak out or to say something that is different.

And that's a huge problem.

It's a huge problem in this country that is something that everyday Americans do not want.

You do not want these investigations being driven by the Twittersphere or being driven by sort of inklings that happen.

You want it to be done carefully.

You want it to be done thoughtfully.

I don't know anything about these probes, but if a career prosecutor or an agent with the Federal Bureau of Investigation or anybody looks at it, they're going to want to do so carefully and with the appropriate guardrails to make sure that it's not being abused.

LAURA BARRON-LOPEZ: When you look back at the prosecution that you led into the Capitol riot and all of the work that you, as well as other FBI -- DOJ and FBI officials did, what do you want the public to understand about this investigation and those prosecutions?

GREG ROSEN: What happened on that day was horrific on a number of levels.

And one of the takeaways of what happened on January 6, 2021, was not simply that there was violence.

It was not simply that it was a protest rung amuck, which is something I have heard.

It was a full-blown, full-scale riot, which happened to coincide, intentionally so, with the peaceful or what was supposed to be the peaceful transfer of power from one administration to the next.

It had nothing to do with who the incumbent was.

It had nothing to do with who the incoming president was.

It had to do with the use of force against the United States government and a mob that assaulted what is arguably the most important legislature in the history of the world.

So my takeaway is, that type of political violence just cannot occur in this country.

LAURA BARRON-LOPEZ: President Trump is now comparing ongoing protests against ICE, against the deportation actions he's taken to insurrections, to the January 6 insurrection.

Does that undermine at all the work that you did, the convictions that you and your team sought?

GREG ROSEN: I don't know if it undermines it.

I don't think they're comparable.

The -- what happened on January 6, as we described it in briefings and argued before courts, was sui generis.

It was unique.

It was one of a kind.

And it was one of a kind because of not just the sheer violence we saw and the amount of people that were there and the amount of officers that were hurt, but it was also because of when it was occurring, which was during the Electoral College certification.

Other protests have and unfortunately perhaps will devolve into violence, depending on what the issue is.

That is also deplorable.

You cannot have circumstances where people are using force against police officers who are doing their job.

That is a consistent drumbeat, and I will be consistent about that.

But protests in isolation or violence in isolation is not what we saw on January 6, 2021.

LAURA BARRON-LOPEZ: Greg Rosen, thank you for your time.

GREG ROSEN: Thanks for having me.