Jurors also convicted Rivera, 23, of burglary with assault or battery while armed on Monday.
The jury deliberated about 16 hours over four days before returning the verdict for Rivera, who admitted in a videotaped confession to police days after Taylor's death that he fired the fatal shot after kicking in the bedroom door.
At the trial, he said on the witness stand that his confession was given only under police pressure and amid purported threats to his family.
Rivera had faced a first-degree murder charge, but jurors chose to convict him of a lesser included offense instead.
“Jury having found you guilty on count 1 of the indictment of a lesser of second-degree murder, court will adjudicate you guilty of that,” Miami-Dade Circuit Judge Dennis Murphy said. “And as to count 2, jury having found you guilty of burglary with assault or battery while armed, court will adjudicate you guilty as to that.”
Jurors had asked to re-examine a large amount of evidence as their deliberations extended into the afternoon.
Some jurors told Murphy on Friday that they were having difficulty deciding the fate of Rivera.
Taylor, 24, who was a Pro Bowl safety for the Washington Redskins and former University of Miami star, died from the injuries he received in the botched invasion of his home in November 2007.
A law book was found in the jurors' deliberation room last week, but Rivera's defense attorneys did not ask for a mistrial Friday.
Rivera sat quietly at the defense table with his lawyers after the verdict was announced, showing no reaction or emotion. The courtroom was packed with Taylor and Rivera family members, but there were no outbursts.
Neither prosecutors, Taylor's family nor the family of the football player's girlfriend would comment after the hearing.
The court will reconvene on Dec. 10 at 10:30 a.m. for the pre-sentencing investigation report, and a sentencing date will be discussed at that time.
Rivera, who was 17 at the time of the slaying, could be sentenced to life in prison.
In the confession, Rivera said the group of five young men, all from the Fort Myers area, had driven to Taylor's house planning to steal large amounts of cash he kept inside. They thought Taylor would be out of town at a game against Tampa Bay, but didn't realize until it was too late that he was home with a knee injury. Taylor's then-girlfriend, Jackie Garcia Haley, and their 18-month-old daughter were also home at the time. They were not hurt.
Four other men were also charged in the case and three will be tried later. Venjah Hunte, 25, pleaded guilty to second-degree murder and burglary charges in a deal that calls for a 29-year prison sentence.
Testifying in his own defense, Rivera claimed it was Hunte who brought the 9mm handgun and who shot Taylor. Rivera insisted that he was not told about the burglary plot until the group was driving across Alligator Alley toward Miami, and that he stayed in the car outside Taylor's house the whole time.
The murder weapon was never found. Police say it was stuffed in a sock and thrown into the Everglades.
Taylor was shot in the upper thigh, damaging his femoral artery and causing massive blood loss. Witnesses say Taylor was shot when he confronted the group with a machete outside his bedroom. A medical examiner said he was essentially dead on arrival at a hospital on Nov. 26, 2007, although doctors did manage to restart his heart for a while.
Aside from Rivera's confession, police found shoe prints outside Taylor's home that matched sneakers some in the group were wearing that night. Witnesses testified Rivera was seen driving a rented black Toyota Highlander believed used in the crime, and another witness said the group of five had burglary tools when they came to her house after Taylor was shot.
Taylor, a first-round Redskins draft pick in 2004, signed an $18 million contract with the team and was becoming one of the NFL's top defensive players when he was slain. Several witnesses, including Garcia Haley, testified that he liked to keep large amounts of cash around his Miami house.
One of the men charged in the slaying, 25-year-old Jason Mitchell, attended a birthday party a few weeks earlier at the house for Taylor's half-sister, Sasha Johnson — who lived in Fort Myers and knew Rivera. She testified that Taylor gave her a purse containing $10,000 in cash at the party, which was witnessed by all the guests.
That event put the wheels in motion for the burglary plot, witnesses said. Rivera himself testified that some in the group thought they would get between $100,000 and $200,000 to split up.
Also charged and awaiting trial are Mitchell, Charles Wardlow, 24, and Timothy Brown, 22.
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