Shayanna Jenkins, 24, was released on her own recognizance, though prosecutors had asked for a $5,000 bail, the Attleboro (Mass.) Sun Herald reported.
Hernandez' fiance is his high school sweetheart and the mother of his infant daughter, the report said.
The perjury charge comes in the Bristol County grand jury investigation into the June 17 killing of Odin Lloyd of Boston.
Lloyd was a semiprofessional football player in Boston, and was dating Jenkins' sister, the Sun Herald said. He socialized with Hernandez before he was shot dead in the North Attleboro Industrial Park, near Hernandez' home.
Jenkins' lawyer, Janice Bassil, told the court her client had immunity in the case, that the prosecution was "overreaching."
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