A bitter separation and parenting battle involving the astronaut Anne McClain led to an unusual accusation last year: Ms. McClain’s ex-wife accused her of improperly accessing her bank account from the International Space Station.
But after a lengthy investigation, federal prosecutors said on Monday that the former spouse, Summer Worden, had lied to investigators about some relevant details, and that a federal grand jury had indicted Ms. Worden on charges that could result in up to five years in prison.
The indictment, returned in February but unsealed this week, alleges that Ms. Worden opened the bank account earlier than she had told investigators, and that she had not changed her login credentials until months later than she had claimed.
The case represented an unprecedented allegation of a crime in space, which experts say could become less unusual as living and working in space becomes more routine. The current case raises questions, for example, about whether records of Ms. McClain’s internet usage from space could be subpoenaed in court to help aid in Ms. Worden’s defense.
Both women have decorated pasts. Ms. Worden is a former Air Force intelligence officer. Ms. McClain is a West Point graduate who became a commissioned Army officer and flew more than 800 combat hours in the Iraq war before joining NASA in 2013.
Ms. McClain remains a lieutenant colonel in the Army and could be in line to be the first woman to walk on the moon.
The indictment, unsealed in Texas, charges Ms. Worden with two counts of making false statements to NASA’s Office of Inspector General and to the Federal Trade Commission. Ms. Worden had made complaints to both agencies accusing Ms. McClain of identity theft.
Ms. Worden filed for divorce in the months after opening a personal bank account in April 2018 and then accused Ms. McClain of accessing it in January 2019, when Ms. McClain was on the International Space Station.
Ms. McClain has said through a lawyer that she continued to use the account after the divorce filing, including from the space station, as she had done throughout the relationship. She said she was continuing to make sure the family’s finances were in order — with Ms. Worden’s full knowledge — even though they were separated. She said Ms. Worden had never told her that the account was off limits.
Federal prosecutors said they concluded that Ms. Worden had never revoked access.
Ms. Worden said on Monday night that she was shocked by the indictment. She said that while she mistakenly gave investigators the wrong date of her bank account’s opening, she later provided them the correct information.
She said it had been her intent to change her password when she created the new account, but she was not sure if she had done so.
“I didn’t misrepresent anything,” Ms. Worden said.
Either way, Ms. Worden said, she did not believe it was appropriate for Ms. McClain to continue to try accessing her finances amid a parenting dispute and divorce battle.
Much of the couple’s conflict revolved around Ms. Worden’s son, who was born about a year before the women met. Ms. Worden had not allowed Ms. McClain to adopt the child, even after their 2014 marriage, but Ms. McClain petitioned a local court in 2018 for shared parenting rights and “the exclusive right to designate the primary residence of the child” if the parties could not reach a mutual agreement, according to records.