Attorney General Jeff Sessions said on Wednesday that he reserves the right to jail journalists, “if we have to.”

Here's his exchange with Sen. Amy Klobuchar (D-Minn.) during a Senate Judiciary Committee hearing:

KLOBUCHAR: Will you commit to not putting reporters in jail for doing their jobs?
SESSIONS: Well, I don't know that I can make a blanket commitment to that effect. But I would say this: We have not taken any aggressive action against the media at this point. But we have matters that involve the most serious national security issues, that put our country at risk, and we will utilize the authorities that we have, legally and constitutionally, if we have to.
Maybe we — we always try to find an alternative way, as you probably know, Sen. Klobuchar, to directly confronting a media person. But that's not a total, blanket protection.

There is a lot of missing context here that Sessions would have been wise to include, if he were interested in avoiding panic.

Sessions appeared to be reiterating a warning he issued in August, when he said that as part of the Justice Department's effort to prosecute government workers who make illegal disclosures of classified information, “one of the things we are doing is reviewing policies affecting media subpoenas.”

Note that we're talking about prosecutions of government workers, not reporters. How could such charges land journalists in jail? Well, because there is no federal shield law that protects journalists from demands to reveal confidential sources, reporters can be subpoenaed — compelled to tell investigators who leaked classified information to them.

A reporter who refuses to comply with a subpoena can be jailed in contempt of court.

That's what happened in 2005 to Judith Miller, then of the New York Times. Miller spent almost three months in jail because she refused to identify the government source who had leaked the name of CIA operative Valerie Plame.

A grand jury investigating whether the leak of Plame's name violated a federal law against disclosing the identities of covert agents had issued a subpoena demanding that Miller reveal her source. The probe sought to determine whether the leak was a retaliation against Plame's husband, former diplomat Joseph C. Wilson IV, who had publicly questioned the George W. Bush administration's justification for invading Iraq.

Sessions said in August that the same tactic used against Miller remains at his disposal now, and he seemed to be doubling down on Wednesday, when he said that in “matters that involve the most serious national security issues,” the Justice Department “will utilize the authorities that we have, legally and constitutionally, if we have to.”

The concern, voiced by Klobuchar, is that the Trump administration might not exercise adequate restraint. Klobuchar said she is “really concerned because of the president's recent communications about FCC licensing and some of the media content.”

She was referring to this:

Trump's tweets misrepresented the way FCC licensing works. National networks such as NBC do not hold broadcast licenses; individual stations do.

But the expressed sentiment suggested that the president is interested in penalizing news outlets — not for breaking any laws but for coverage that he considers “partisan, distorted and fake.” It is not a big leap to wonder whether a president who would consider using his power in that way might abuse the subpoena authority of his Justice Department to hold the threat of jail time over journalists' heads.

Sessions didn't exactly try to assuage such worries in his testimony.