FAIRFAX, Va. — The home health aide who prosecutors say was shot and wounded by alleged Alexandria serial killer Charles Severance repeatedly asked her attacker who he was even as he fired at her, according to her eyewitness account that was made public for the first time in court filings this week.

The aide later gave police a vivid description of her assailant — helping to generate a sketch that bears a resemblance to Severance — but she did not definitively pick him out of a lineup, and prosecutors say they do not know whether she will be able to identify him in court.

Prosecutors and defense attorneys revealed the new details in recent court filings that debate what the aide should or shouldn’t be allowed to testify about at trial. The aide, who worked in the home of a music teacher prosecutors say Severance shot and killed, is one of the most pivotal witnesses in the case, though authorities had not previously divulged what she saw and remembered.

Severance, 54, is charged with murder in the February 2014 slaying of music teacher Ruthanne Lodato, the November 2013 fatal shooting of regional transportation planner Ronald Kirby and the 2003 killing of real estate agent Nancy Dunning.

Prosecutors have alleged that Severance was motivated by a child custody case that went against him and a hatred for Alexandria’s elite, and suggested that he knocked on the doors of his victims at random before shooting them at their homes in broad daylight.

He is scheduled to go to trial in October.

The aide, who is identified in the filings only as “D.F.,” worked in Lodato’s home, caring for her elderly mother.

According to the filings, she was in the bathroom with Lodato’s mother when she heard Lodato talking to someone at the front door.

The aide heard a pop and a scream, according to the filings, and when she went to the door, she ran into a gunman.

According to her chilling account in the filings, the aide fell to the floor, and the assailant shot at her two or three times with a gun half hidden by his sleeve. All the while, according to the filings, the aide asked her attacker who he was.

The aide later described her attacker to police in detail. Based on information she provided, officials generated a sketch that bears a resemblance to Severance. It seems, though, that she never identified Severance definitively — at least so far.

Shown a photo lineup of six bearded men that included Severance, the aide ruled out five of them, according to court filings. Of Severance’s photo, she said her attacker’s hair and beard were not as long, according to the filings.

Prosecutors seemed to view that as a victory, noting that Severance’s hair would have grown between the attack in February and his arrest in March. Defense attorneys asserted, though, the evidence was only a “quasi-identification,” and noted the aide “could not positively identify” Severance as the suspect.

Defense attorneys argued in the recent court filings that the lineup should be inadmissible as evidence at trial, and the aide should further be prevented from identifying Severance as her attacker in court.

Prosecutors argued that the lineup should be admitted, and the aide should be able to identify her attacker in court — even as they acknowledged that they did not know whether she would be able to. They said they had not shown the aide a picture of Severance since the lineup, and she had purposefully avoided news reports on the matter.

A defense attorney for Severance declined to comment for this story, as did the Alexandria commonwealth’s attorney.

The dispute is scheduled to be taken up Thursday at a catch-all motions hearing in Fairfax County Circuit Court, where the case was moved over concerns about seating a fair jury.

Prosecutors and defense attorneys are also haggling over the circumstances — if any — under which jurors should be told that some witnesses in the case were given polygraph tests, among a number of issues.