A former D.C. social services worker pleaded guilty Friday to participating in a more than two-year scheme to bilk the city government out of about $800,000 in public benefits.

Aretha Holland-Jackson, 45, admitted in federal court that she used her access to the Department of Human Services’ computer system to set up public assistance for nearly two dozen phony beneficiaries. Using fake names and Social Security numbers, Holland-Jackson obtained government ID cards that she and others used to withdraw food stamps, cash and other public benefits from ATMs, according to prosecutors.

Allison Holland, Holland-Jackson’s 47-year-old sister, also admitted involvement in the scheme. Prosecutors said Holland, of Cheltenham, used three of the fake cards, then saved cash for her sister in a shoebox.

The scheme, which lasted from February 2011 to September 2013, cost the D.C. government at least $783,876 in public benefits mostly intended for low-income families, according to the U.S. attorney’s office. “This prosecution shows how committed we are to aggressively pursuing government employees who think they can get away with robbing taxpayers of their hard-earned money,” U.S. Attorney Ronald C. Machen Jr. said in a statement.

U.S. District Judge Amy Berman Jackson set a sentencing date of May 7 for the sisters, who each pleaded guilty to conspiracy to commit wire fraud. Holland-Jackson likely faces a sentence of 33 to 41 months in prison, while Holland is expect to receive a sentence of 15 to 31 months in prison, authorities said.

After the hearing, Michael Lasley, Holland-Jackson’s attorney, said his client was “hooked into the situation” by an unnamed co-conspirator who died last March. Lasley described the co-conspirator as a family friend who provided Holland-Jackson with prescription pills and devised the false identities that she later processed in her capacity at the department. “What happened, more than anything else, is he developed a scheme, and she went along with it,” Lasley said.

Holland-Jackson was arrested in September after using one of the debit cards to withdraw about $700 from an ATM on H Street NE, authorities said. She was in possession of eight cards at the time.

Holland-Jackson was fired the next day, said DHS spokeswoman Dora Taylor. Court papers say Holland-Jackson had worked as a social services representative in the department’s Office of Medical Assistance since February 2005.

Authorities began to investigate after the department received a tip last year that mail had been sent to a fake beneficiary, said Christa Phillips, DHS’s chief accountability officer. A DHS employee could not find any record of the beneficiary, setting off a fraud investigation that eventually involved federal prosecutors and D.C. police. Phillips said the discovery was made possible by “new systems that detect fraud a lot sooner” within the department. “That’s why the staff was doing their due diligence,” she said.

The case against Holland-Jackson originated in D.C. Superior Court. Machen’s office chose to pursue the case as a federal conspiracy involving Holland-Jackson and her sister. As part of her plea agreement, the charges against Holland-Jackson in D.C. Superior Court were dismissed.

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