A Massachusetts judge has authorized a subpoena so lawyers for former New England Patriots player Aaron Hernandez can identify an anonymous tipster who claimed one of the jurors who convicted Hernandez of murder may have been "untruthful" during jury selection.

Judge Susan Garsh ruled Friday that Verizon can be subpoenaed to determine the identity of the tipster who called attorney James Sultan in April, after Hernandez was convicted in the 2013 killing of Odin Lloyd.

The judge said the caller's credibility can be determined only by first learning her identity.

Sultan says the tipster called him from a blocked number and said the juror was present for a discussion about a Boston double murder Hernandez is also accused of committing.

The jurors weren't told about that case during the trial.