President Donald Trump’s effort to install loyalist U.S. attorneys without Senate approval could sink the Justice Department’s criminal cases against former FBI Director James Comey and New York Attorney General Letitia James.

In recent weeks, federal courts in New Jersey, Nevada and California have ruled that unusual maneuvers by the Justice Department to appoint Trump’s unvetted prosecutors violated federal law. Their rulings are a prelude to the potential disqualification of a fourth Trump-backed U.S. attorney: his former personal lawyer Lindsey Halligan, who brought the charges against Comey and James.

The rulings against the three interim U.S. attorneys point to the likelihood, legal experts say, that Halligan’s high-profile prosecutions of Comey and James could collapse alongside her own appointment. That’s because the judges concluded that despite the invalid appointments, the prosecutions brought by those disqualified U.S. attorneys could survive because — unlike the Halligan-led prosecutions — they were also approved by career prosecutors who were validly appointed.

Halligan, however, secured the indictments of Comey and James by herself, an indication that career prosecutors in the Eastern District of Virginia resisted bringing the cases. Critics have described the prosecutions as political retribution, noting that Trump has vowed revenge against Comey and James for their involvement in previous investigations into him.

If Halligan’s appointment is deemed invalid, “there are serious questions about whether the indictment in the Comey and James prosecutions could stand,” said James Pearce, a former Justice Department appellate attorney and senior member of special counsel Jack Smith’s team.

Pearce emphasized that in the California, Nevada and New Jersey cases, judges focused on the role that career attorneys played in securing indictments. The disqualified U.S. attorneys played minimal roles in those cases, he said.

“It seems far less clear whether that rationale would apply in the [Virginia] prosecutions,” Pearce added.

Jacqueline Kelly, a former federal prosecutor in the U.S. Attorney’s Office for the Southern District of New York, said the demise of those cases coupled with Halligan’s disqualification “could be a long-term consequence of a decision that was made for short-term reasons.”

“It becomes a clash of priorities, in a sense,” she said. Kelly predicted that if the efforts to disqualify U.S. attorneys and dismiss indictments brought by them are successful, the Trump administration might reprioritize Senate confirmations. “They may refocus on … trying to persuade senators into voting for particular appointments instead of trying to do this end-run around the appointments clause.”

A spokesperson for the Justice Department didn’t immediately respond to a request for comment.

A federal judge is set to hear arguments this month on the legality of Halligan’s appointment, which came two days after Trump pressured Attorney General Pam Bondi to quickly prosecute his political adversaries. At the time, the top prosecutor in the Eastern District of Virginia, Erik Siebert, had reportedly resisted pressure to bring criminal charges against James, and he resigned in the wake of social media attacks by Trump.

Halligan secured the indictments against Comey and James, both prominent Trump foes, within her first three weeks on the job. But because Bondi appointed Halligan as interim U.S. attorney after having previously appointed Siebert to the interim role, both Comey and James have argued that Halligan was installed in violation of federal law and should be disqualified.

Meanwhile, legal challenges against other interim U.S. attorneys continue across the country. The case against Alina Habba, Trump’s pick to be New Jersey’s top federal prosecutor, is the most advanced. A panel of appeals court judges is set to rule on whether to uphold a district judge’s determination in August that she is serving illegally because she remained in charge after her 120-day interim appointment expired. The three judges on the panel, including a Trump appointee, appeared skeptical of her appointment during oral arguments last month.

Should the government lose at the 3rd Circuit Court of Appeals, it could appeal the decision to the Supreme Court. But even if Habba is ultimately deemed to be invalid, that may not jeopardize the prosecutions of the defendants who challenged her appointment, since their indictments were secured with the assistance of career prosecutors.

And it may not affect some of Habba’s most notable cases, including the prosecution of Democratic Rep. LaMonica McIver following a scuffle outside a federal immigration facility. That’s because McIver was indicted in June, during Habba’s tenure as interim U.S. attorney, prior to when the Trump administration used unconventional tactics to keep her in the job.

In September, a federal judge ruled that the top federal prosecutor in Nevada, Sigal Chattah, was disqualified from handling cases. The judge said she couldn’t supervise the prosecutions of any defendants who challenged her authority “or any attorneys in the handling of these cases.”

U.S. District Judge David Campbell, a George W. Bush appointee, didn’t dismiss the indictments because they were signed by career prosecutors in addition to Chattah. The government is appealing Campbell’s ruling to the 9th Circuit Court of Appeals.

And in California, a federal judge disqualified Bill Essayli, the top prosecutor in the Los Angeles area, saying he should have departed the post by July 31. U.S. District Judge J. Michael Seabright, a George W. Bush appointee, also concluded that despite Essayli serving invalidly, indictments he brought should not be dismissed because they were signed by legally-appointed career prosecutors in his office.