When veteran social worker Olivia López took a job at a detention center for immigrant families about an hour's drive south of San Antonio in October, she was energized.
At Karnes County Residential Center, she would be working with a Central American immigrant population she knew not only from her work in Texas, but also from growing up the daughter of a farm foreman in California's Central Valley.
The job paid $70,000, about as much as López, 57, of Corpus Christi, had been earning teaching social work after a dozen years in the business. She called it "a dream come true."
But within six months, López had resigned, complaining that the work she was asked to do was unethical and endangered her license.
On Tuesday, López is scheduled to appear at a forum on family detention hosted by the Congressional Progressive Caucus and Democrats from the House Judiciary Committee.
The Obama administration expanded family detention after tens of thousands of immigrant families crossed the Southwest border last summer, most of them from Central America. The government went from one 95-bed detention center in Pennsylvania to three, the two newest and largest in Texas, with a total of 3,700 beds by year's end.
About 1,700 parents and children are being held at three family detention centers in Leesport, Pa., and Dilley and Karnes City, Texas.
Last week, opponents of family detention scored a major victory when a federal judge in Los Angeles ordered the Obama administration to show by Aug. 3 why the government should not be found in violation of conditions for children's detention laid out in a 1997 settlement — a ruling that could force the government to end family detention.
López worked at the center in Karnes City, an oil-field town surrounded by ranches and pastures at the heart of the state's Eagle Ford shale-fracking boom.
While there, she said, she became increasingly concerned that detainees' medical and psychological problems were being downplayed or ignored, and that those who protested conditions were being isolated in what she believed was an attempt to marginalize their complaints.
"I knew I could no longer remain," she said in an interview Monday. "My licensure was at risk."
The detention center is operated by the nation's second-largest prison company, Boca Raton, Fla.-based Geo Group, and overseen by U.S. Immigration and Customs Enforcement.
Geo officials said they have "strongly refuted" any allegations of misconduct or mistreatment at the facility, according to spokesman Pablo Paez, who said in an email that the center provides "high-quality care in a safe, clean and family-friendly environment."
Nina Pruneda, an ICE spokeswoman based in San Antonio, said in a statement that the agency "is committed to ensuring that individuals in our family residential centers receive timely and appropriate medical healthcare."
López, whose story began emerging this week ahead of Tuesday's forum, said her work at the detention center forced her to do things that as a social worker she regarded as unethical.
In some cases, she said, the company told her to omit some information from the immigrants' files, including complaints about medical conditions, such as a woman with recurrent headaches who had a family history of brain aneurysms.
On Dec. 22, she wrote the company directive in her notebook during a staff meeting, "ICE: We don't tell them anything."
Because of the restrictions, López said, she couldn't do her job.
"There is no therapy for women whose children are not in school because there is no child care, so they bring the children to session," she said.
Instead of discussing the women's histories of sexual assaults and abuse, which could help their asylum cases, she said, "we spoke in generalities."
She said she saw a 5-year-old Central American girl, who had been raped and physically abused during the journey, lose weight at the detention center and start wearing diapers.
When she reported the girl's conditions to her boss, a psychologist, she said he discharged the girl with a note saying she was sleeping and eating better. When López submitted a note in response reiterating that the girl had lost weight, another supervisor told her she was mistaken.
"I can discern an increase and a decrease" in weight, López said.
When dozens of women at the detention center staged a hunger strike this spring, several of the leaders reported being placed in isolation in the medical unit with their children, an allegation López corroborated.
López remembers her supervisor announcing that the warden wanted the hunger strike "ring leaders" placed in isolation.
Looking back, López says, she should have called state Child Protective Services.
By April, López said she was having heart palpitations because of work stress and finally resigned on April 2.
Geo officials refused to respond specifically to López's allegations, but Paez noted that a Homeland Security inspector general's investigation found no evidence of sexual abuse or harassment at the detention center.
The Karnes City facility has "created an open and transparent policy of allowing visits to the center by the public, elected local and national officials, federal officials from ICE and other government agencies, as well as nongovernmental organizations," Paez said.
After her resignation, López contacted the dean of the school of social work at her alma mater, the University of Texas at Austin, who put her in touch with immigrant advocates and eventually the office of U.S. Rep. Zoe Lofgren (D-San Jose), an outspoken critic of family detention who is expected to be among those at Tuesday's forum.
López plans to return to teaching and says she has no regrets.
"I have to be able to sleep at night," she said. "My dad was an immigrant and those moms and kids could be me."
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