Hernandez has pleaded not guilty in the killing of Odin Lloyd in June 2013. Testimony in the case lasted for more than two months, and deliberations have stretched on for nearly 35 hours.
Superior Court Judge Susan Garsh sent jurors home late Tuesday afternoon with reminders to avoid all news on the TV, radio, newspaper or other media and to not to discuss the case with anyone.
"Please do not do any research of any kind," she told them.
The 12 jurors must reach a unanimous verdict. In addition to the murder charge, the jurors are also deciding whether to convict Hernandez of weapon and ammunition possession charges.
They have sent several notes, none related to the murder charge. They have asked for clarification on the possession charges, for permission to take a morning smoke break and for a list of the 439 exhibits in the case.
They did not send any note Tuesday, coming into the courtroom only briefly at the beginning and end of the day.
Shayanna Jenkins, Hernandez's fiancee, sat in the front row behind him, and they exchanged glances during the few minutes he was in court. Across the aisle, her sister, Shaneah, sat with Lloyd's mother and other family members.
Hernandez has been kept in a cell near the courtroom during the deliberations.
Prosecutors never offered a clear motive for why Hernandez would want to kill Lloyd.
The defence has acknowledged that Hernandez witnessed the killing but questioned why he would put his career on the line to kill someone. He had a $40 million contract with the Patriots at the time.
Prosecutors argued that Hernandez thought no one would believe he did it.
If convicted of first-degree murder, Hernandez would be sentenced to life in prison without parole. If convicted of second-degree murder, he would get life with the possibility of parole after 15 years.
Regardless of what happens in the Lloyd case, Hernandez, who grew up in Bristol, Connecticut, will not be released from custody. He has pleaded not guilty to murder in Boston, where he is accused of the drive-by killing of two men in 2012. Prosecutors say he felt disrespected after one of the men bumped into him and spilled his drink.
Prosecutors in the Lloyd case were not permitted to mention the 2012 shootings.