WASHINGTON – The federal indictment of former FBI Director James Comey could face significant legal challenges – and potential dismissal – due to questions about how the Trump administration appointed the prosecutor who obtained it, constitutional law experts and Democratic lawmakers say.

One former Justice Department official, Ed Whelan, says there’s “a fatal legal flaw” in Comey’s Sept. 25 indictment because the department lacked the legal authority to appoint White House official Lindsey Halligan as the U.S. attorney for the Eastern District of Virginia.

In that capacity, Halligan was the only prosecutor to sign off on the grand jury indictment against Comey on two counts of lying to Congress and obstructing an official proceeding.

“I think the appointment is invalid, and therefore the indictment is invalid,” said Whelan, the principal deputy assistant attorney general for legal counsel under former President George W. Bush, told USA TODAY in an Oct. 6 interview.

If that’s the case, Whelan and others said, it could knock out the case before it gets to trial. Comey is scheduled to be arraigned, and to enter a plea, Oct. 8 in the Alexandria, Va. district, just outside the capital.

Whelan, who holds the Antonin Scalia Chair in Constitutional Studies at the Ethics and Public Policy Center, first made his claim in two Sept. 26 blog posts for National Review, a conservative magazine, the day after Comey’s indictment.

Liz Oyer, the former Justice Department pardon attorney under Trump, said she believes "there's a strong argument that she was not lawfully appointed."

“And if she was not lawfully appointed, the indictment would likely be invalid," Oyer told USA TODAY, "since she's the only person who signed the indictment.”

Oyer also said that because the statute of limitations to bring these particular charges against Comey expired Sept. 30, “That means that if this indictment is thrown out, it cannot be fixed” or resubmitted.

“Comey’s lawyers will certainly raise this argument,” Oyer said, “and if the judge agrees, he could throw out the case before it even gets to a jury.”

Some Trump critics are taking up the argument. irginia Sen. Tim Kaine, a Democrat, referenced Whelan's blog posts on X when he posted: "Here's a question. Can Donald Trump even appoint an interim U.S. Attorney in the Eastern District of Virginia to carry out his retribution spree?"

While Comey has said he is innocent and will fight the charges, a lawyer representing him had no comment to USA TODAY about whether they plan to attack the validity of the indictment – or Halligan’s appointment – in court.

Justice Department spokesman Chad Gilmartin also had no comment on the validity of Halligan's appointment and the Comey indictment. Halligan’s office did not respond to requests for comment and the White House referred questions about the matter to DOJ.

Halligan brought the charges after Attorney General Pam Bondi tapped her to replace another Trump administration appointee, Interim U.S. Attorney Erik Siebert.

President Donald Trump says he fired Siebert − Siebert says he resigned − after the prosecutor declined to seek an indictment of Comey. He and his legal team reportedly believed there was a lack of sufficient evidence.

The appointment of Halligan − a former insurance lawyer with no prosecutorial background who was previously a personal defense attorney for Trump and then aide in his White House − occurred just days before the five-year statute of limitations was to run out on Sept. 30 on charges accusing Comey of making false statements to Congress back in September 2020.

Her appointment also came soon after Trump personally took to social media to demand that Comey be indicted, along with other of his perceived political enemies.

In a Sept. 20 post on Truth Social, Trump addressed Bondi publicly, saying Comey was "guilty as hell," without explaining what Comey was allegedly guilty of. "We can’t delay any longer," and "JUSTICE MUST BE SERVED, NOW!!!" Trump said.

Only one interim US Attorney appointment allowed?

According to Whelan, the Justice Department cannot lawfully appoint a second interim U.S. attorney after appointing a first one whose term has expired.

He cites Section 546(d) of Title 28 of the United States Code, which authorizes an attorney general to appoint an interim United States attorney for a term of 120 days. After that, only “the district court for such district may appoint a United States attorney to serve until the vacancy is filled.”

In Siebert’s case, his term expired 120 days after his Jan. 21 appointment by Acting Attorney General James McHenry, on or about May 21. After that, Whelan said, Eastern District of Virginia judges appointed him to continue to serve.

Whelan also cited as evidence a Nov. 13, 1986, memo by conservative Supreme Court Justice Samuel Alito, who at the time was a senior Office of Legal Counsel lawyer in the administration of President Ronald Reagan. OLC, as the office is called, guides the Justice Department and the broader U.S. government on what’s legal.

Alito wrote that “after the expiration of the 120-day period further interim appointments are to be made by the court rather than by the Attorney General.”

“Thus it would appear that Congress intended to confer on the Attorney General only the power to make one interim appointment; a subsequent interim appointment would have to be made by the district court” overseeing that prosecutorial jurisdiction, Alito wrote.

If Trump fired Siebert, 'That makes the office vacant'

Pro-Trump lawyer Trent McCotter disagreed with Whelan's analysis. He responded to Whelan on X that because Trump fired Siebert, “That makes the office vacant.”

“If you're right,” he told Whelan, “the AG's appointment power would literally never reset once 120 days expire.”

Siebert’s appointment by the court “reset the 120 day clock,” argued McCotter, a former Justice Department prosecutor. And “upon his removal, the clock starts ticking once a new person is appointed by AG.”

Also, McCotter wrote on X, his analysis of the federal law in question is that the Attorney General can appoint a new U.S. Attorney even after judges make their own appointment.

Confusion over interim versus acting US attorney?

It’s possible that the Trump administration appointed Halligan, as “acting” U.S. Attorney rather than interim U.S. Attorney, Whelan and other legal experts say.

But the administration has never said so, and DOJ spokesman Gilmartin had no comment on whether the Trump administration appointed Halligan in that temporary capacity for the suburban Washington district that hears some of the nation’s most consequential cases.

Whelan argues Halligan couldn't have been appointed acting U.S. attorney either, because a 2003 OLC opinion – that he wrote himself – requires that she have served first as a Senate-confirmed officer in another position, “and she hadn’t been in the Department of Justice at all, much less for the 90 days required.”

"It would be weird if they're now saying she was appointed as acting" U.S. attorney, Whelan told USA TODAY.

This article originally appeared on USA TODAY: Does James Comey indictment have 'fatal flaw'? Some legal experts say so.

Reporting by Josh Meyer, USA TODAY / USA TODAY

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