MELISSA BLOCK, HOST:

The watchdog for the nation's intelligence agencies says it has uncovered classified emails from the private server of Hillary Clinton. The inspector general has asked the FBI to look into the possible compromise of sensitive information. At the same time, Republicans on Capitol Hill are renewing their call for Clinton, the frontrunner in the Democratic presidential race, to hand over that server. Joining us to talk about the latest controversy is NPR justice correspondent Carrie Johnson. And Carrie, first, what problems did this watchdog identify?

CARRIE JOHNSON, BYLINE: The inspector general for these intelligence agencies, Melissa, wrote lawmakers this week, and he raised concerns that classified or secret information had been sent or received via messages on these Hillary Clinton accounts. It may not have been marked that way at the time, but a look back by these intelligence officials suggests those messages should have been marked as secret. And the concern for the watchdog is that Clinton may have that sensitive material and more on her server and on a copy that's currently with her lawyer. But the watchdog doesn't have the authority to demand Clinton turn over that information.

BLOCK: This is a - the private email server that she used as secretary of state. How does the Justice Department get involved now, if it does?

JOHNSON: A bit complicated because the Justice Department has contradicted itself about what it's doing. First, Justice confirmed there was a call for a criminal probe. Then, a few hours later, Justice said it was a request to investigate the possible compromise of sensitive information. After hours and hours of calls, I'm told this is something called a section 811 Referral. That refers to a part of an intelligence law that was passed by Congress after some pretty big-time American spies were busted.

BLOCK: So a referral - what's the purpose of that if it's not to actually prosecute people criminally?

JOHNSON: These are reports that other agencies use to tell the FBI when classified information has been released or is being released inappropriately, potentially to agents of foreign powers or foreign governments. The goal is to get out in front of the release of classified information and stem the damage early. But there's no word yet on whether the FBI or the Justice Department will launch any kind of investigation. Even so, Democrats and Republicans on the Hill have been fighting all day over what it says and what it means.

BLOCK: And what is Hillary Clinton saying?

JOHNSON: At a campaign event today at New York University, the former secretary of state says she's turned over to the State Department already 55,000 pages of emails. She says she will make herself available to answer questions from House Republicans. And she says we're all accountable to the American people to get the facts right, and I will do my part. But there was no commitment to hand over that private server.

BLOCK: And so, Carrie, what happens now?

JOHNSON: We can expect much more congressional investigation by House Republicans in particular, more time of processing some of those pages of emails by the State Department for possible public release into late this year and, of course, more questions to dog Hillary Clinton all along on the campaign trail.

BLOCK: That's NPR justice correspondent Carrie Johnson. Carrie, thanks so much.

JOHNSON: You're welcome. Transcript provided by NPR, Copyright NPR.