"As the clerk was collecting evidence out of the jury room he discovered (a) Florida criminal law rules book sitting on the table in there. 2010 edition,” Judge Dennis Murphy said.
The book, which was found Thursday, should not have been in the jury room, Murphy said. Jurors are not supposed to conduct their own research on a case.
Rivera, 23, is charged with first-degree murder and burglary in the 2007 shooting of Taylor. The NFL star died from the injuries he received in a botched invasion of his home.
The judge said of the discovery of the law book, "That raises an issue of potential jury misconduct so I must ask the parties what they want to do about it?”
State prosecutors warned that if the defense did not ask for a mistrial now it could be taken that Rivera had waved his rights to ask for a mistrial. Rivera's attorneys said they would wait to raise the issue after a verdict.
"So you are not asking the court for a mistrial at this point,” Murphy asked. The answer was no.
The judge asked Rivera if he agreed with his lawyers, and the defendant said he did.
Jurors reconvened Friday morning for their third day of deliberations. They went home for the weekend without reaching a verdict. The case is set to resume Monday morning.
The court adjourned early Thursday so jurors could go home and enjoy Halloween celebrations with their children.
Prosecutors say Rivera shot Taylor while he and four other men from Fort Myers attempted to burglarize Taylor's Palmetto Bay home. Taylor, who they thought would not be home, confronted them with a machete and was shot. He died the next day from his injuries.
Rivera, who was 17 at the time, faces life in prison if convicted.
One of the suspects, Venjah Hunte, has already pleaded guilty in the crime. The others will head to trial later.
The judge answered some questions from jurors Friday afternoon, two of which dealt with how to determine to what degree the accused was involved in the charges against him, if jurors find that he was.
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