"It does not indicate that the F.B.I had no grounds for contradiction to investigate Mr. Flynn," she wrote. "It does not suggest that F.B.I.'s interview of Mr. Flynn – which led to the allegations of false statements – was illegal or unjust. It does not support Mr. Flynn's false statements were not material."
McCord continued, "And it does not support the Justice Department's assertion that the continued prosecution of the case against Mr. Flynn, who pleaded guilty to knowingly giving material false statements to the FBI, & # 39; would not serve the interests of justice. & # 39; "
McCord's op-ed is a blatant rebuke of Barr and the DOJ political appointees who took over the Flynn case from career prosecutors. McCord spent nearly 20 years at the DOJ, rising to top positions in the Obama administration and the first months of the Trump administration.
In these senior roles, McCord was involved in the internal DOJ deliberations on how to handle the Flynn debate in January 2017, when senior Trump officials were caught in a public lie about Flynn's ties with Russia.
Her comments come less than a week after the Justice Department dropped the case against Flynn, whose lie about his contacts with Russia prompted President Donald Trump to fire him three years ago. Flynn later turned to Trump, pleaded guilty to lying, and cooperated in the Russia investigation. But he turned his course last year, began to attack the Russia investigation and tried to undo his guilty plea.
"I do my duty according to the law, as I see it," Barr said. He reiterated the legal justification for bringing the case presented in the filing, saying that "a crime cannot be created here."
Barr also said the FBI "had no basis for a preliminary investigation against Flynn at that stage," adding that "people sometimes plead things that turn out not to be crimes."
In addition to McCord, the filing drew swift criticism from former FBI officials who had worked on the case and supported the investigation of Flynn.
The court must still formally approve the DOJ's request to dismiss the case.
CNN's Marshall Cohen and Katelyn Polantz contributed to this report.