WASHINGTON — CNN secretly fought an attempt by the Justice Department to seize tens of thousands of email logs of one of its reporters, the network disclosed on Wednesday, adding that the government imposed a gag order on CNN’s lawyers and its president, Jeff Zucker, as part of the legal battle.

The disclosure — including that CNN ultimately agreed to turn over “a limited set of email logs” involving the reporter, Barbara Starr — was the latest to recently come to light in a series of aggressive steps that federal prosecutors secretly took in leak investigations late in the Trump administration.

It is also the second such episode known to have spilled over into the early Biden administration. CNN struck a deal with prosecutors to settle the matter on Jan. 26, it said, and the government only recently lifted the gag order.

Last week, a New York Times lawyer revealed a similar fight — and a gag order imposed in March. The government abandoned its battle for the Times reporters’ email logs on June 2 without having obtained any, asking a judge to quash a Jan. 5 order for them.

In recent weeks, the Justice Department has also disclosed separate Trump-era seizures of phone records of the same Times and CNN reporters, along with several reporters at The Washington Post. In the fallout, President Biden barred the department from seizing reporters’ communications records in an attempt to identify their sources — a major policy change from a practice that was permitted under prior administrations of both parties.

Testifying before senators about the Justice Department’s budget on Wednesday, Attorney General Merrick B. Garland declined to criticize the Trump-era department for pursuing such records in leak investigations.

“I’m not casting blame,” he said, adding that the decisions to seize records were made “under a set of policies that have existed for decades.”

But calling investigative journalism about the government “vital to the functioning of our democracy,” Mr. Garland highlighted the administration’s new approach of not seeking reporters’ communications when it investigated leaks, calling the policy “the most protective of journalists’ ability to do their jobs in history.”

The Justice Department regulation governing seizures of reporters’ records in hunts for their sources was tightened by Attorney General Eric H. Holder Jr. after a May 2013 uproar about two leak inquiries, one involving The Associated Press and the other, Fox News.

That regulation generally requires giving news organizations advance notice when prosecutors intend to take such a step, so they can negotiate over its scope or fight in court. But it allows department leaders to make exceptions.

Mr. Garland, who also said he would issue a memo detailing the new policy soon, has scheduled a meeting with leaders of the three news organizations for Monday.

Press freedom advocates have condemned the department for its actions, and renewed that critique after CNN’s disclosure.

“Government efforts to access journalists’ records always raise serious press freedom concerns, but the gag order makes this case unusual and particularly disturbing,” said Jameel Jaffer, the director of the Knight First Amendment Institute at Columbia University.

He added: “The courts have made clear in other contexts that these kinds of gag orders are rarely consistent with the First Amendment. Gag orders impede public scrutiny that’s important to ensuring that government agents aren’t abusing their powers.”

While the Trump Justice Department sought the reporters’ records in 2020, each of the three leak investigations involved disclosures — and communications records — from 2017.

CNN said its general counsel, David Vigilante, received a court order in July 2020 seeking data about two months of Ms. Starr’s emails from 2017 — along with a gag order that prevented him from disclosing the matter. Other lawyers for CNN and Mr. Zucker were eventually also told, but gagged.

The initial order, Mr. Vigilante said in a separate account CNN published online, demanded data that would cover more than 30,000 emails, including about 26,000 that were internal and so could not have had anything to do with a leak investigation. In September, the network asked a court to narrow the scope of the order, he said.

A magistrate judge in the Eastern District of Virginia — Theresa Carroll Buchanan, CNN said — said at an Oct. 7 hearing that the Justice Department should narrow the order, but two days later the department provided her with a secret filing its lawyers could not see.

Two weeks later, Mr. Vigilante said, she ordered CNN to comply with the original, full demand for Ms. Starr’s email records. In November, the network appealed that decision, and the following month Judge Anthony Trenga, a district court judge, held a hearing and then directed the department to narrow the scope of its request.

Mr. Vigilante quoted the judge as expressing skepticism about the government’s explanation for why Ms. Starr’s email logs were relevant, portraying prosecutors’ theory as based on “speculative predictions, assumptions and scenarios unanchored in any facts.”

He also said the judge said at the hearing, “The requested information by its nature is too attenuated and not sufficiently connected to any evidence relevant, material or useful to the government’s ascribed investigation, particularly when considered in light of the First Amendment activities that it relates to.”

On Jan. 15, just before the Trump administration left office, the department asked the judge to reconsider, CNN said. Then on Jan. 26, six days after Mr. Biden’s inauguration, the network’s lawyers sat down with prosecutors and struck a deal to produce what a CNN reporter described as “a limited number of email records — essentially records that the government already had from its side of these communications.”

That deal ended the fight, CNN said, although the executives who knew about the fight remained under gag order until recently. The network also said it did not know that Ms. Starr’s phone records and data from her personal email account had separately been seized until the Justice Department notified her in May.

“None of those accounts were held by CNN or its parent company, AT&T,” CNN said.

Mr. Vigilante also noted that “the only reason I got notice at all was because the Justice Department had to serve the secret order on CNN’s parent company, as Ms. Starr’s work email resided on its servers.”

By contrast, because The Times has contracted with Google to handle its email system, the Justice Department was initially able to serve the Jan. 5 court order on the tech company without the newspaper’s knowledge. Google fought for the right to tell The Times, in accordance with a contract, and in March the Justice Department asked a judge to permit a handful of Times lawyers and executives to know — but extended the gag order to them.

The disclosures about CNN and The Times have left open the question of what happened in the leak investigation involving The Post.

That newspaper has said that when its reporters were told last month that the Justice Department had seized their phone records, they were also told that prosecutors had obtained a court order to seize the reporters’ email logs but did not collect any such records.

A spokeswoman for The Post has said there was no gag order on its executives. But she declined on Wednesday to say whether the newspaper controls its own email system or an outside company does.

On Tuesday, lawyers for The Times asked a court to unseal two sets of the Justice Department’s filings in support of the attempted records seizure and gag order.

After the CNN disclosure, Patrick Toomey, a senior staff lawyer at the American Civil Liberties Union, called for legislation — not just executive branch policy changes — to protect investigative journalists’ ability to protect their confidential sources.

“The Justice Department shouldn’t be spying on journalists and shouldn’t be issuing gag orders to media organizations,” he said. “Amidst these repeated revelations, the White House and Congress need to be working to establish a long-lasting ban on demands for this sensitive information, in order to protect journalists and the news reporting our democracy depends on.”

Katie Benner contributed reporting.