A woman who accused Mayor Eric Adams of sexually assaulting her in 1993 told nine people about the encounter and documented her account in emails years ago, her lawyer said in a legal filing on Monday.

The filing did not contain specific details about what the woman, Lorna Beach-Mathura, said to each person or when she said it. But it said that she told seven of the nine people that he had assaulted her before the Adult Survivors Act took effect in 2022. That legislation opened a window for people to bring lawsuits over past sexual assaults.

Ms. Beach-Mathura provided two emails she sent in 2021 about the assault when Mr. Adams was running for mayor and before she had the ability to sue him under the new state law, according to the filing, which was a letter written to the judge, Richard G. Latin, of the State Supreme Court.

Mr. Adams has denied the allegations, and his allies have sought to attack her credibility and her history of filing lawsuits. Ms. Beach-Mathura’s past comments to people about the assault and written records could be central to the lawsuit.

The mayor’s legal team has been battling with her lawyer, Megan Goddard, in court documents ahead of Ms. Beach-Mathura’s deposition, which is expected in September.

The mayor’s lawyer, Alex Spiro, confirmed that the emails were provided to the defense, but he said that they did not contain proof to support the accusations. He noted that they were sent to the rival campaign of Andrew Yang and to The New York Post when Mr. Adams had already become a prominent figure.

Ms. Beach-Mathura said she worked with Mr. Adams at New York City’s transit police bureau and asked him for help with a promotion, according to the 26-page complaint. When he requested oral sex and she declined, he forced her to touch his penis and ejaculated on her leg, the complaint said.

The lawsuit is pending against Mr. Adams at a time when he is facing a federal investigation into his campaign fund-raising and running for re-election in a competitive Democratic primary next year. The New York Times reported last week that Mr. Adams and his 2021 campaign were served with a new round of grand jury subpoenas in the federal investigation in July.

Mr. Spiro, who has represented Elon Musk and other high profile clients, wrote a letter to the judge last week arguing that Ms. Beach-Mathura was not providing enough information during the discovery process and “continued to exhibit a pattern of delay and obfuscation.”

His letter also said that the plaintiff had not provided the date that the assault occurred in 1993 and that she appeared to be trying to “backfill the details of her story,” including asking for Mr. Adams’s shift schedules from that year.

Ms. Goddard’s letter said it was the mayor’s legal team that was not responding to requests for information, including “basic employment records” about whether Mr. Adams and the plaintiff worked together at the transit police department.

Ms. Goddard wrote that Mr. Spiro’s letter contained “false, inflammatory, and irrelevant statements” and accused the mayor of seeking to discredit her client “using every means available to him.”

The lawsuit seeks $5 million and names the Police Department and the Guardians Association, a fraternal organization of Black police officers, as defendants. Mr. Adams was a leader in the Guardians at the time the assault was said to have occurred.

Ms. Beach-Mathura was “sickened” by Mr. Adams’s run for mayor, the lawsuit said, and “appalled” that he became “so powerful and that he might become even more so.”

She now lives in Florida and has a history of filing lawsuits. She wrote a 52-page self-published book that includes a petition she filed in the United States Supreme Court in 2013 when she represented herself in a lawsuit against the Miami-Dade County Public Schools Board over workers’ compensation.

Mr. Adams has strenuously denied the allegations, and the mayor’s office has sent statements from his political allies criticizing the lawsuit.

“This did not happen — it did not happen,” Mr. Adams said at a news conference in March. “I don’t recall ever meeting this person during my time in the Police Department.”

Two of the mayor’s friends from the transit police, Charles Henry and Cliff Hollingsworth, said in interviews that they worked with the plaintiff, whose name was then Lorna Beach, at Transit Police District 34 in Coney Island in the 1980s.

Mr. Adams has said that he began his police career there in 1984. The lawsuit said that the plaintiff worked there from 1981 to 1986 and ran into Mr. Adams years later and asked him for help with the promotion.

Mr. Henry said he believed that Mr. Adams and Ms. Beach worked in Coney Island at the same time, though he said he could not be certain. There were not many Black employees at the time, which is why he remembers Ms. Beach.

Mr. Henry said he did not believe the allegations against the mayor: “I know Eric, and he would never do that.”