Aaron Hernandez Update: Perjury charge against Shayanna Jenkins, girlfriend of ex-NFL star, needs more details, judge tells prosecutors

Shayanna Jenkins, right, in court in Fall River, Mass. Wednesday, Nov. 6, 2013. CBS Boston

(CBS/AP) FALL RIVER, Mass. - Massachusetts prosecutors must provide more detail about how the girlfriend of Aaron Hernandez allegedly lied in testimony to a grand jury that indicted the former New England Patriots player on a murder charge, a judge ruled Wednesday.

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Defense attorney Janice Bassil said in Fall River Superior Court she is "at a loss" for how prosecutors believe Shayanna Jenkins lied to the grand jury because the perjury indictment isn't specific.

Jenkins, who attended the proceeding but did not address the court, pleaded not guilty to a single count last monthand is free on personal recognizance. She did not comment after the hearing.

Bristol County prosecutors said at Jenkins' arraignment that she lied before the grand jury, including about disposing of a box from the basementof the North Attleborough, Mass., home she shared with Hernandez, at his request.

Prosecutors say Jenkins told grand jurors she couldn't recall where she threw out the box, which she put in a trash bag along with baby clothes. It's not clear what the box contained.

Jenkins was granted immunity before she testified to the grand jury.

Bristol County Assistant District Attorney William McCauley said Wednesday that most of Jenkins' testimony, on that and other topics, was "not credible." Her intention was "to protect, to cover up and to assist in keeping evidence from our reaches," he said.

Bassil has said there is no evidence Jenkins lied and that the prosecution simply doesn't believe her.

Judge Susan Garsh ruled that prosecutors must provide more detail to the defense by Dec. 2. Jenkins is due back in court Jan. 6.

Hernandez has pleaded not guilty in  the killing of Odin Lloyd, a 27-year-old semipro football player who was dating Jenkins' sister. He is being held without bail.

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