Updated June 8, 2022 at 1:35 PM ET

Dozens of women and girls who were sexually abused by the former gymnastics doctor Larry Nassar have filed administrative claims against the FBI over its investigation.

U.S. Women's National Team gymnasts Simone Biles and Aly Raisman and gymnast Maggie Nichols are among the more than 90 claimants who are seeking damages in excess of $1 billion from the bureau.

The group says the FBI failed to properly follow up on credible claims against Nassar in 2015, after which victims continued to face sexual abuse at the hands of the now-disgraced doctor.

The Justice Department announced in May that it wouldn't prosecute two FBI agents who, according to a government watchdog, lied and hid their missteps from authorities.

"My fellow survivors and I were betrayed by every institution that was supposed to protect us - the US Olympic Committee, USA Gymnastics, the FBI and now the Department of Justice," Olympic gold medalist McKayla Maroney said in a statement.

"It is clear that the only path to justice and healing is through the legal process," she added.

Why are these women and girls filing claims against the FBI?

According to a press release from Manly, Stewart & Finaldi — one of the law firms representing the plaintiffs — the FBI had a chance to stop Nassar's abuse in 2015 when it first received allegations against him.

Instead, FBI officials were "grossly derelict in their duties" by declining to interview gymnasts, failing to transfer the complaint to Michigan and lying to Congress and authorities within the bureau, attorneys said.

Most of the claimants were abused by Nassar after 2015, the press release noted.

A report by Inspector General Michael Horowitz released last summer found that two FBI officials made a series of mistakes in their handling of the allegations against Nassar, including failing to follow up with several victims and lying about what they had done.

One FBI agent involved in the Nassar investigation retired and another was fired by the bureau.

Is this a lawsuit?

No. These are administration complaints filed under a law called the Federal Tort Claims Act.

It allows people who suffer some kind of injury because of the wrongful or negligent behavior of a federal employee to file a claim against the government.

If the agency denies the claim or doesn't respond after six months, the complainant can then file a civil lawsuit in U.S. District Court.

A separate group of 13 women and girls who were also abused by Nassar filed similar claims in April.

Jamie White, an attorney in that case, said he saw parallels with a settlement the Justice Department reached with survivors and family members of the Parkland, Florida, school shooting, who had sued the FBI for failing to act on tips that the perpetrator was prone to violence.

What has the FBI said?

The FBI declined to comment on the recent filings.

A spokesperson pointed to FBI Director Christopher Wray's comments during a hearing of the Senate Judiciary Committee in September, in which survivors who were abused by Nassar were also present.

"I'm sorry for what you and your families have been through. I'm sorry that so many different people let you down, over and over again," Wray said. "And I'm especially sorry that there were people at the FBI who had their own chance to stop this monster back in 2015 and failed."

Wray added that the FBI's missteps were "inexcusable" and that the bureau was working to ensure such mistakes don't happen again.

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