An anonymous tipster who exchanged letters with former New England Patriots player Aaron Hernandez before his murder trial isn't credible.

That's according to a Fall River Superior Court judge who on Friday denied Hernandez's lawyers' motion to further examine the tipster's claims.

Hernandez was convicted of the 2013 killing of Odin Lloyd. He's awaiting trial on separate murder charges in Boston.

Hernandez's lawyer said in court documents the tipster said a juror was involved in a discussion about the Boston killings.

The judge's decision said the tipster testified in October that the juror hadn't participated in the discussion at a 2014 party.

Hernandez was awaiting trial when a fellow inmate, the tipster's father, encouraged Hernandez to exchange letters with his daughter.

Court documents say her father sold some of the letters.