Amin “flatly denies” the allegations, lawyer Scott R. Grubman said in a statement.

“DR. Amin has always treated his patients, including those in ICE detention, with the utmost care and respect,” said Grubman.

Lawyers for the women claim ICE tried to deport many of them before they can help investigators, even this week. At least three federal lawsuits were filed on behalf of three of the women who said they were almost deported. They argued that ICE would take revenge on them and violate their initial adjustment rights if the deportations were carried out.

“The deportation of these witnesses – especially if none of them have received independent physical or mental health assessments from medical experts – means the de facto destruction of evidence,” wrote lawmakers, including Senate Minority Leader Charles E. Schumer (DN.Y .).

The letter was addressed to acting ICE director Tony Pham, as well as the three federal agencies – the Justice Department, the FBI, and the Office of the Inspector General of Homeland Security – who conducted the investigation, which first opened in September.

ICE spokeswoman Danielle Bennett said in a statement to the Washington Post that ICE is “fully cooperating” with the investigation, including recording interviews for the probe and notifying investigators of plans to deport or transfer Amine’s ex-patients. She added that the agency does not comment on ongoing legal disputes and is responding to congressional letters through official channels.

“Any implication that ICE is trying to hinder the investigation by removing respondents is completely wrong,” said Bennett.

A request for comment from the Justice Department was forwarded to the US law firm for the Southern District of Georgia, which declined to comment. Neither the FBI nor the DHS Inspector General’s Office responded to emails asking for comment.

The U-Visa program, first launched in 2000, is open to undocumented immigrants who work with law enforcement after witnessing or falling victim to a violent crime. Individuals can obtain temporary legal residence and an avenue to US citizenship, although there has been a growing backlog and a decline in applications in recent years.

Elora Mukherjee, a professor at Columbia Law School, said certification of such a visa was the “minimum basic protection” federal investigators can provide to inmates willing to cooperate with their probe.

“These women take enormous risks to live up to what has happened to them,” she said in an interview. “And everyone on the investigation team should make sure that as many women as possible come up and speak up.”

The letter from the Democrats in Congress also called for investigators to put in place a “clear and transparent process” for women incarcerated in Irwin to identify themselves as witnesses and question all women who “credibly” allege medical abuse. In addition, according to lawmakers, any woman who accuses investigators should be allowed to re-enter the country and apply for a U-Visa.

National attention fell to Irwin in September after a whistleblower to a nurse at the facility, Dawn Wooten, alleged that a doctor later identified as Amin had subjected immigrant detainees to unwanted hysterectomies.

Their claims of widespread unwanted sterilization were quickly verified. The hospital where Amin practiced said only two women in ICE detention had been referred for hysterectomies.

However, allegations against Amin have received significant attention from lawmakers, news organizations and human rights groups. As Maria Sacchetti of the Post reported, an independent team of medical experts, including nine board certified obstetricians, reviewed more than 3,200 pages of medical records from 19 women in Irwin who were allegedly ill-treated. They noted that what they consider to be a worrying pattern of inadequate care was misdiagnosis and a failure to seek informed consent for surgery and other procedures.

The Inspector General of the DHS initiated his investigation at the end of September. In the weeks since the investigation began, the lawyers said, ICE has deported several of the women who set off the alarm, including Ana Adán Cajigal, who has often led the speakers. From inside the facility, the 25-year-old spoke to investigators and lawmakers and often acted as a translator between lawyers, reporters and other detainees.

Adán, who has been detained in Irwin for more than eight months, said she was examined by Amin on September 14 for what she believed to be a sexually transmitted disease. Allegedly, Amin silently and forcibly inserted a non-lubricated camera into her vagina, ignoring her signs of distress. He told her she needed birth control pills for a cyst the size of a toenail on her left ovary. But when she was taken to another doctor weeks later, they told her she did not have such a cyst, she said in the lawsuit.

About two weeks later, Adán was deported. But it wasn’t until Tuesday – nine days after her interview with investigators – that ICE abruptly informed her that she would be deported to Mexico the next day. After a team of lawyers intervened at the last minute, Adán is now suing ICE after being almost deported. The lawsuit is a final effort to prevent her own deportation.

At least two other women have filed lawsuits after similar incidents. According to her lawsuit, Adán’s story “fits into a pattern of rapid deportation of witnesses as soon as they identify as willing to exercise their rights to testify.”

Grubman denied all of Amin’s allegations of wrongdoing, noting that his client operates outside of the ICE facility and is not involved in immigration proceedings. He said his client has “fully cooperated with the ongoing investigation” and is “confident that he will be fully exonerated”.

Maria Sacchetti contributed to this report.