The panel reached a decision after almost four hours of deliberations.
Jurors had two options: The death penalty or life in prison.
Judge Donald Jacobsen followed the jury's recommendation and sentenced Williams to life.
The family of Officer Arnulfo Crispin pushed for the death penalty. They walked away disappointed."Obviously we're not happy with the (sentence)," Frankie Crispin said, Arnulfo's brother. "The fact that he'll be by himself for the rest of his life, it brings some closure."
Frankie told reporters the death penalty is the only option for a man like Williams who murdered an innocent police officer."We will come to realize that you know what, he has no life from now on. He's going to be looked up forever," he said.
After the sentencing, Williams' lawyer, Byron Hileman, said he considered the sentence a relief."Anytime you save a client's life, that is something very important," he said.
He told reporters he will file an appeal in the coming weeks.
Closing arguments in the penalty phase of the murder trial wrapped up shortly before 10:30 a.m. Tuesday.
After being denied a request for a mistrial, Hileman argued that the shooting death of Crispin was not a premeditated act. "This was a sudden chance encounter that led to tragedy," Hileman said.
Hileman also took issue with the prosecution's contention that Williams was a gang member. He told the jury that there is "no credible evidence that Kyle Williams was in a gang."
He ended with a plea for life. "Kyle Williams has good qualities. His life should be preserved," Hileman said.
On Monday, jurors heard impact statements from family members and others for more than five hours.
"There is not a day I don't think about Arnulfo and his love," said Brenda Crispin, Arnulfo's sister.
With tears flowing, she explained to the jury her family's torment and anguish over his loss. Her brother was murdered on her son's birthday.
"For JJ's birthday now I always remind him of how Arnulfo loved him. He was taken on his birthday and it breaks my heart to watch my son stare at his photo," she said.
Monday was the last chance for the defense to try to spare Williams' life.
Three of his former teachers took the stand to talk about his character and personality.
"He stood out in my mind because he always came in my room each day with, 'Good morning Mrs. Smith, how are you?'" said Michelle Smith, who works at Lakeland High School.
Another teacher, Grace Ford, said she visited him in jail as many as 10 times.
"I visited him because I care about him," she said. "He has good inside of him."
Williams' mother described her son as a responsible person who paid for his own phone and helped pay the family's bills.
Williams chose not to take the stand.
Jurors found 21-year-old Williams guilty last Thursday of first-degree murder.