AMNA NAWAZ: During his race for the White House, President Donald Trump pledged to expand Second Amendment rights nationwide.

Now his administration is taking major steps to roll back gun restrictions put into place for public safety.

Our justice correspondent, Ali Rogin, has more.

ALI ROGIN: Amna, earlier this year, the Justice Department unveiled a major road map to reduce regulations on purchasing firearms, arguing the changes would -- quote -- "modernize gun policy."

Now the department is also taking more targeted actions, going after Democratic-led states for their own gun restrictions.

For more on the Trump administration's efforts to broaden Second Amendment rights, I'm joined now by Chip Brownlee.

He's a staff writer at The Trace covering federal gun policy.

Chip, thanks so much.

Welcome to the "News Hour."

I want to ask you first about these rollbacks that the DOJ has announced.

What rules and policies would be impacted here?

CHIP BROWNLEE, The Trace: Yes, so the ATF, the Bureau of Alcohol, Tobacco, Firearms, and Explosives, has proposed a range of rollbacks, about three dozen in total.

I would say most of the proposals that they have are actually pretty administrative.

They update and modernize some of the processes that gun dealers use.

But there are a couple of things in there that are pretty significant.

One that has gotten a lot of criticism from the gun reform side of things is a rule that was intended to close the gun show loophole.

The Trump administration has proposed rolling back that rule.

And then there are some other things like reducing regulations on short-barrel rifles and bump stocks, bump stocks being the -- one of those devices that was used in the Las Vegas mass shooting in 2017.

And some of those regulations are actually just bringing things back in line with what the Supreme Court has said in terms of things like the bump stocks.

But the big thing is the rule that was intended to close the gun show loophole.

ALI ROGIN: There's another rollback that's caused some controversy, and that is reducing the restrictions on people with mental illness to own a firearm.

That's upset some gun safety groups.

What kind of risks are involved with that rollback?

CHIP BROWNLEE: Well, the ATF -- the ATF itself actually said that there's a risk that rolling that rule back could result in mass casualty events.

I don't know how big of an impact that's going to be, because, right now, federal law is that if you were involuntarily committed into a psychiatric institution, for example, you would lose your gun rights, and that remains the law.

This is kind of clarifying essentially that, if you were voluntarily entering yourself into a facility, that wouldn't count, and then some other things about, if you have been previously ruled as not able to handle your own affairs, kind of removing some of that stuff.

But this is a regulation and a rule that's been back and forth between the Trump administration and the -- going back to the Obama administration.

So I don't know that that one will have as big of an impact as some people are saying it will.

ALI ROGIN: And I should mention that acting Attorney General Todd Blanche has disavowed some of the conclusions in that ATF study, saying... CHIP BROWNLEE: Yes.

ALI ROGIN: ... they really don't indicate there's any increased risk.

I also want to ask you about these lawsuits that the Department of Justice is pursuing against bans in the states of California and Virginia against certain types of firearms.

What led to those suits?

CHIP BROWNLEE: Yes, so ever since the Trump administration took over the Department of Justice, they have really kind of refocused the Civil Rights Division to focus on gun rights and enforcing gun rights.

This is the same division that was previously enforcing voting rights and desegregating schools going back to the 1960s.

And, since last year, the Trump administration has been focused on gun rights.

And they brought seven different lawsuits against jurisdictions across the country.

One of them, the most recent one is against California's handgun roster require -- regulations, which is basically a list of approved handguns that people can buy, and then another regulation in California essentially banning Glocks, because there's a piece of a Glock that makes it more kind of susceptible to being outfitted with a switch and turned into a machine gun.

And then, in Virginia, the Department of Justice has sued the state over its assault weapons ban.

And that's one of a number of different lawsuits the department has brought against assault weapons bans, also in Denver and D.C.

and some other places as well.

I'm not aware of the Civil Rights Division really enforcing gun rights at any point before this.

This new section has since brought seven lawsuits against jurisdictions across the country, so this is really a new thing that we haven't seen before.

ALI ROGIN: And the Supreme Court has said, next session, they're going to take up two cases in which one state and one local assault weapons ban are being discussed.

What are the implications if they rule against those bans?

CHIP BROWNLEE: Yes, so there are about a dozen states across the country that have assault weapons bans, and then some municipalities and local jurisdictions that have them.

So, if the Supreme Court shut down the assault weapons bans in this case, that would mean that most of those, if not all of those across the country would also be unconstitutional.

The two here that the Supreme Court has taken are assault weapons bans in Connecticut and in Cook County, which is Chicago.

And those laws have been on the book since the 1990s, and now the Supreme Court is likely going to rule them unconstitutional.

This is -- again, so you would have a dozen states across the country that could lose their assault weapons bans, a lot of these laws passed in the wake of mass shootings across the country.

ALI ROGIN: Chip Brownlee with The Trace, thank you so much.

CHIP BROWNLEE: Thank you.