HARRISBURG — No criminal charges should be filed against a onetime Pennsylvania legislator accused of sexually assaulting a woman in 2015 while she was incapacitated, a Dauphin County grand jury has recommended.

The grand jury, impaneled this year to investigate the allegations against former State Rep. Brian Ellis (R., Butler), cited the woman’s delayed reporting of the incident and memory lapses of key witnesses, among other factors, the woman told The Inquirer and the Caucus this week.

Dauphin County District Attorney Fran Chardo on Friday declined to comment, and the full context of the grand jury’s reasoning, outlined in a report expected to be publicly released Monday, was not immediately available.

Ellis, 50, through his lawyers, has denied the allegations, which were first reported by The Inquirer and the Caucus in January. Lawyers for Ellis could not immediately be reached on the latest development.

A grand jury hears evidence in criminal cases and recommends whether charges should be filed, but the final decision is the prosecutor’s. Chardo is likely to follow the panel’s recommendation.

The woman, a state employee, said Chardo’s office told her late Thursday about the grand jury’s recommendation. The Inquirer and the Caucus do not identify victims of sexual assault unless they agree to make their names public.

In the interview, the woman said she believes the grand jury’s decision was driven by the testimony of a critical witness — a onetime friend who was with her the night of the alleged assault. The friend, she said, either said she did not remember key details or gave inconsistent testimony.

The woman called it a betrayal: “I understand that this is not cut and dried. But to have a friend — to have that person derail this.… The process is already so difficult. I can’t understand it."

The friend is not named in the grand jury report, and her lawyer on Friday declined comment.

Chardo’s office launched a criminal investigation into the allegations against Ellis early this year. In March, the woman filed a formal complaint against Ellis with a House lawyer, as well as the chamber’s ethics committee.

Shortly after, Ellis announced his resignation. In a statement, he admitted no wrongdoing, but said stepping down was in the best interest of his family, constituents, and his own health.

The woman has alleged that she was assaulted in October 2015 in Ellis’ Harrisburg apartment. Earlier that evening, she said, she had been out with her friend at a restaurant and bar. There, she said she had fewer than two drinks — and then suffered a near-total memory loss for the next 12 hours. She has said she believes she was drugged.

Ellis was not at that bar, but at another restaurant nearby. The woman eventually ended up there. The next morning, she said, she woke up in Ellis’ bed disoriented and in pain. She said he told her they had sex. She has said she has only fleeting moments of memory after the two drinks.

The woman said Ellis had previously pursued her and she had made it clear she had no interest in him. She said that she did not report the alleged assault at the time because she felt traumatized, ashamed, and confused. She did go to a hospital a day later and was treated for a concussion and body pain.

In the interview this week, she said she was glad that Ellis no longer held a position of public trust, which she believes will prevent him from using his power to hurt women.

She also said she remains resolute that what happened to her that night in October 2015 was rape. “It happened,” she said. “He did this.”