Charges were dropped Friday against the last person accused in a widespread sex-trafficking ring run by a St. Paul family.

Prosecutors dropped charges against Elizabeth A. Alexander, 26, of St. Paul, because it became apparent that she was a victim, said Dennis Gerhardstein, spokesman for the Ramsey County attorney’s office.

Alexander had been charged with one count of conspiracy to commit sex trafficking in connection with a ring run by her ex-boyfriend, Antonio Washington, his brother and their two uncles.

All four men have been convicted in the case.

“Our understanding of her role in this whole criminal enterprise changed over the course of the prosecution of the Washington brothers and uncles,” Gehardstein said. “She obviously testified truthfully throughout the process, and we got a better picture of who she is, and we feel that her role was more that of a victim than a perpetrator.”

Alexander was not given a deal for her testimony, he said. She was released soon after she was arrested and charged in April.

Antonio and Otis Washington were convicted of posting hundreds of online ads selling sex with several women, some as young as 15, who were coerced, threatened and assaulted into a life authorities described as “modern-day human slavery.”

Their uncles, Calvin and Robert Washington, pleaded guilty to helping their nephews.

The family preyed on young vulnerable girls — some diagnosed as bipolar or mentally disabled.

Authorities believe the family’s sex-trafficking stretches further back and involves more victims, but they were charged and convicted of recent crimes involving a handful of girls and women.