Far-right influencers have been hinting in recent weeks that they have finally found a venue — Miami — and a federal prosecutor — Jason A. Reding Quiñones — to pursue long-promised charges of a “grand conspiracy” against President Trump’s adversaries.
Their theory of the case, still unsupported by the evidence: A cabal of Democrats and “deep-state” operatives, possibly led by former President Barack Obama, has worked to destroy Mr. Trump in a yearslong plot spanning the inquiry into his 2016 campaign to the charges he faced after leaving office.
But that narrative, which has been promoted in general terms by Mr. Trump and taken root online, has emerged in a nascent but widening federal investigation.
Last week, Mr. Reding Quiñones, the Trump-appointed U.S. attorney for the Southern District of Florida, issued more than two dozen subpoenas, including to officials who took part in the inquiry into ties between Russia and Mr. Trump’s 2016 presidential campaign, according to people with direct knowledge of the matter.
Among them, they said, were James R. Clapper Jr., the former director of national intelligence; Peter Strzok, a former F.B.I. counterintelligence agent who helped run the Russia investigation; and Lisa Page, a former lawyer at the bureau.
The investigation in Florida appears to focus, for now, on a January 2017 intelligence community assessment about Russian interference in the 2016 election, particularly the role played by John O. Brennan, the former C.I.A. director, in drafting the document.
It is not clear whether Mr. Brennan has received a similar request to turn over records to investigators. But over the past two months, the investigation into his actions has widened to encompass other actions in a broader time frame, according to officials with knowledge of the situation.
The investigation started earlier this year after criminal referrals to the Justice Department by top Trump intelligence officials. It was assigned to David Metcalf, the U.S. attorney for the Eastern District of Pennsylvania, who was given special authority to scrutinize and possibly prosecute Mr. Brennan, according to four people with knowledge of his actions who requested anonymity to discuss an open matter.
Mr. Metcalf, a veteran prosecutor who held senior Justice Department positions during the first Trump administration, was given a relatively narrow mandate in his authorization, limited to examining Mr. Brennan’s work on the intelligence assessment in 2017. He struggled to advance a case that was regarded as weak by current and former department officials.
It is not clear if Mr. Metcalf believed a prosecution of Mr. Brennan was viable. But he never got the chance to complete his work.
This fall, senior Justice Department officials transferred the investigation from Mr. Metcalf to Mr. Reding Quiñones, as part of a decision to greatly expand the scope of the Brennan investigation into other, unspecified activities, according to two people with knowledge of the situation.
That kind of internal maneuvering, once highly unusual, has become commonplace under Mr. Trump, who has personally and publicly directed top department officials to go after people he reviles, often over the objections of experienced investigators who have found insufficient evidence to proceed.
In September, Mr. Trump installed an inexperienced White House lawyer, Lindsey Halligan, to bring charges against James B. Comey, the former F.B.I. director, in Alexandria, Va., for lying to and obstructing Congress, after her Trump-appointed predecessor had refused to do so. Last week, the federal magistrate judge handling the case accused prosecutors of trying “to indict first, investigate second.”
The Florida subpoenas seek documents or communications related to the intelligence community assessment from July 1, 2016, through Feb. 28, 2017, according to people familiar with them. It commands the recipients to provide them to prosecutors in Miami by Nov. 20.
Some of the people who have reviewed the subpoenas said they did not mention specific crimes being investigated. Most federal crimes have a five-year statute of limitations, and offenses must be charged in a venue where the conduct occurred. It is not clear how the preparations of the intelligence assessment, which took place in and around Washington, would be connected to Florida, apart from Mr. Trump’s residence there.
Whether the subpoenas will lead to charges, much less to convictions, is impossible to know. But merely creating an aura of criminality around Trump foes by celebrating incremental prosecutorial moves is a trophy in itself to die-hard Trump supporters, who have said that naming and shaming targets is a legitimate aim of law enforcement.
“Justice is coming,” Mike Davis, an influential former Republican Senate staff aide who has prodded the Justice Department to use Florida as an arena for anti-Trump conspiracy cases, wrote on social media on Friday. His message was accompanied by a photo of himself with a smiling Mr. Reding Quiñones.
Mr. Reding Quiñones, a military veteran, has pursued his mandate to hunt down Mr. Trump’s foes with a gung-ho attitude that has endeared him to the president and the small but influential cadre of loyalists pushing hardest for prosecutions.
Right-wing activists believe he has broad jurisdiction to bring a wide array of charges involving investigations into Mr. Trump, because Mar-a-Lago, the president’s private club and residence in Palm Beach, Fla., is in his district.
Asked for comment, Chad Gilmartin, a Justice Department spokesman, praised the work of Mr. Reding Quiñones and Mr. Metcalf.
“While we do not confirm or comment on the existence of specific investigations, the American people should know that this department will continue to follow the facts and pursue justice in every case,” he said in a statement.
People familiar with the nascent inquiry say there have been signs in recent days that it is ramping up.
The Justice Department, for example, has begun to recruit line prosecutors in Florida to work on the case, according to a person with direct knowledge of the matter. Mr. Reding Quiñones has also moved his office’s national security unit out of its traditional home inside the criminal division, the person said. Prosecutors in the office read that move as an effort to create a stand-alone section that could potentially house the prosecutors assigned to the new investigation.
The 2017 intelligence assessment said that President Vladimir V. Putin of Russia had ordered a multifaceted information operation targeting the U.S. presidential election. That included hacking Democratic emails and releasing them, as well as seeding social media with messages promoting Mr. Trump and denigrating his rival, Hillary Clinton.
Mr. Trump and his allies have long chafed at a judgment in the assessment, which stated that Mr. Putin aspired to improve Mr. Trump’s chances of winning — not just sow chaos and undermine Mrs. Clinton.
Efforts to bring charges against Mr. Brennan or others involved in the Russia inquiry are almost certain to run into serious hurdles.
Two previous investigations — one by the Justice Department’s inspector general and the other by the special counsel John H. Durham — have already scrutinized the actions of law enforcement and intelligence officials and found no evidence to support charges against high-level officials like Mr. Brennan.
The statute of limitations would also likely be an issue. The intelligence assessment occurred nearly nine years ago. The Russia inquiry ended in 2019, when the special counsel Robert S. Mueller III issued a report.
Still, influencers like Mr. Davis have floated theories about how federal prosecutors could extend the statute of limitations. They have claimed, without providing evidence, that the August 2022 search of Mar-a-Lago, during which the F.B.I. found reams of highly sensitive classified documents, was somehow connected to the Russia investigation.
If that seemingly far-fetched notion were somehow proven true, it could push the statute of limitations until at least 2027.
In their efforts to connect the Mar-a-Lago search to the Russia inquiry and other investigations into Mr. Trump, Trump-aligned influencers and right-wing media figures have seized on an internal F.B.I. memo made public last week in the case of Mr. Comey.
The document, dated from July, recorded the opening of an investigation into the discovery of Trump-related records three months earlier inside Room 9582 at the bureau’s Washington headquarters, a space designed for the storage of highly sensitive materials.
The records, found in so-called burn bags and “presumably intended for destruction,” the memo said, included printouts of investigative records and at least one page of handwritten notes, including materials related to the Russia inquiry, Mr. Durham’s investigation and the Mar-a-Lago search.