Judge Aileen M. Cannon’s surprising dismissal of Donald Trump’s criminal case in Florida could jeopardize not just future special counsels but any federal prosecutor or senior official serving in a temporary position, according to legal experts.

Justice Department officials share that concern, according to people familiar with the situation who spoke on the condition of anonymity to discuss internal conversations. The agency declined to comment.

Cannon ruled last month that special counsel Jack Smith was unlawfully appointed because he was not confirmed for his position by the Senate, tossing the 40-count indictment against the former president for allegedly keeping classified material after leaving the White House and obstructing government efforts to retrieve it. Smith and his team are finalizing their appeal of that decision to the U.S. Court of Appeals for the 11th Circuit, which is due Tuesday.

Legal experts say Cannon’s ruling could be used as ammunition for defense lawyers to challenge indictments or directives from any interim official who is not confirmed by Congress, including acting U.S. attorneys or senior Justice Department officials. It could be years before the potential consequences of Cannon’s opinion are fully understood.

“The decision creates risk elsewhere,” Matthew Seligman, a lawyer at Stanford University’s Constitutional Law Center, said in an interview. He argued before Cannon as an outside legal expert at a hearing in the June that the appointment of Smith was constitutional.

Cannon’s ruling rejected decades of findings by other courts that approved the appointments of special counsels, or similar types of semi-independent prosecutors. She wrote that Congress had not granted the attorney general authority to appoint someone with as much power as Smith without Senate approval.

Attorney General Merrick Garland tapped Smith to take over two separate investigations of Trump in late 2022, days after Trump announced his 2024 presidential campaign. At the time, President Joe Biden, who appointed Garland, was assumed to be running for reelection.

Special counsels have more independence than a typical prosecutor, and Garland said the Trump investigations warranted such an appointment because Trump again was running for president and the cases were so politically fraught.

Months later, Smith secured federal indictments against Trump in Florida, on the classified documents charges, and in D.C., for allegedly trying to obstruct Biden’s 2020 election victory.

Cannon’s ruling, which does not affect the D.C. case, contains one sentence in which the judge suggests her decision would not apply to acting officials. But several legal experts said there’s plenty in her 93-page opinion to suggest that the impact would go far beyond special counsels.

The reasoning she lays out in her opinion draws little distinction, they said, between people in interim positions and special counsels — neither of whom are Senate-confirmed. Attorneys general and other agency heads frequently rely on interim officials when the confirmation process is ongoing.

At the hearing before Cannon, Seligman also raised a different scenario: when non-Senate-confirmed officials fill roles often occupied by officials who do have Senate confirmation. For example, deputy solicitors general often fill in for the U.S. solicitor general to argue cases on behalf of the government before the Supreme Court.

“The implication of the argument that the defendant is offering here is that the principal attorney arguing before the United States Supreme Court on behalf of the United States is unlawfully appointed,” Seligman said then.

It is common for lawyers to debate the potential consequences of major legal rulings, and Cannon’s decision is no different. Some said her opinion, which noted that Smith was not working at the Justice Department when he was named special counsel, suggested that his appointment would be constitutional if he had been an employee of the agency — even if the government position he held was not a Senate-confirmed one. Others disagreed.

Smith worked at the Justice Department earlier in his career but was a war-crimes prosecutor in The Hague at the time of his appointment.

Lawyers who criticized Cannon’s opinion said it creates uncertainty and threatens a key authority the attorney general uses to keep the Justice Department operating. They conceded it would be unusual for other judges to throw out criminal cases because a prosecutor was serving in an acting capacity, but said Cannon’s decision suggests there are some on the benchwilling to take such a leap.

Some legal experts said they see Cannon’s ruling as part of a larger effort by conservative jurists to redraw the lines of power, overturning decades of precedent.

“There seems to be willingness of right-wing judges to say that everything that came before is of no consequence when it comes to determining history and constitutional power,” said Philip Allen Lacovara, the deputy solicitor general during the Nixon administration who later served on the Watergate special prosecutor team. “That means they feel free to overturn anything that has been viewed as acceptable and legitimate based upon a novel and recent view of constitutional allocation of power.”

Right now, Cannon’s decision applies only to the South Florida judicial district in which she serves. Any decision from the three-judge panel at the 11th Circuit in Atlanta would apply to the Southern states that the circuit’s jurisdiction covers, but could also be appealed up to the Supreme Court.

Several legal experts said they could envision a scenario in which a defendant in a different court would use Cannon’s opinion to build an argument that someone acting in an interim capacity had no authority to bring a certain action.

Cannon similarly cited a nonbinding concurring opinion by Supreme Court Justice Clarence Thomas to bolster her reasoning in the special counsel ruling.

Thomas tacked his concurring opinion onto the Supreme Court’s decision on presidential immunity — which involved Trump’s D.C. case, not his Florida case. In the opinion, Thomas questioned the constitutionality of Smith’s appointment, essentially inviting Cannon to tackle the issue.

Cannon then referred to his opinion in her ruling.

Vikram D. Amar, a professor at the University of California at Davis School of Law, said Cannon’s opinion could be read as a legal argument against interim government officials. But he also called her ruling far-fetched, and said he doubts there would be enough like-minded judges on the appeals courts or Supreme Court to uphold it across the nation.

“I don’t think there are five complete rogue actors on the Supreme Court,” Amar said. “It might stimulate other people to make unconvincing arguments in other cases. Will those arguments prevent the work of the Justice Department in the long run? I don’t expect so.”

Joshua Blackman, a constitutional law professor at the South Texas College of Law, was another outside legal expert who argued before Cannon at the hearing this spring. He agreed with Trump’s legal team that Smith’s appointment was unconstitutional.

Blackman said in an interview that he accepted the crux of Cannon’s opinion. He came to the hearing prepared to answer questions about the constitutionality of appointing interim officers, as well as special counsels, he said. But Cannon didn’t delve deeply into that issue.

This case is not the first to bring up questions about the constitutionality of acting officials taking big roles in government, Blackman said, adding that Cannon’s opinion builds off existing conservative legal theories around non-Senate-approved appointments. Rulings in those other cases, however, have upheld the authority of people acting in temporary roles.

“The reasoning of Judge Cannon’s opinion casts some doubt on acting U.S. attorneys. But that question has been out there for a long time,” Blackman said. “There’s a lot of analysis of her opinion that will spill into other areas of law.”