The Dallas County jury deliberated for more than 10 hours before sentencing him in the killing of Senior Cpl. Mark Nix.
As the verdict was read, Mr. Ruiz’s mother, Barbara Ruiz, sobbed into a crumbled tissue and turned to her mother for comfort.
Mr. Ruiz, 28, fatally shot Cpl. Nix after a high-speed chase in 2007. Mr. Ruiz testified last month during the guilt-innocence phase of the trial that he thought police were shooting at the car in which he was hiding. The jury did not believe his self-defense claim.
Jurors watched the police dash camera recording of the shooting again Friday. It had been played repeatedly during the trial.
Jurors had two sentencing options: life without parole or death.
During closing arguments, defense attorney Paul Brauchle told jurors that they had to decide whether they believe Mr. Ruiz is going to be a continuing threat, even if locked in prison.
Mr. Brauchle said prosecutors did not prove that Mr. Ruiz would be a violent inmate.
During the past year when Mr. Ruiz has been held in the Dallas County Jail, he has had no discipline problems, Mr. Brauchle said.
“It’s like they are saying, ‘Trust us. We’re from the state. We’re here to kill Wes Ruiz,’ ” he said.
Karo Johnson, another defense attorney, ran at the jury box during his closing arguments holding the same baton Cpl. Nix used to break the window of the car Mr. Ruiz was driving during the incident. He hit the jury box with the baton, causing many jurors to jump.
Mr. Ruiz feared for his life, Mr. Johnson said.
Prosecutor Andy Beach rejected the defense attorneys’ assertions of nonviolence and reminded jurors that Mr. Ruiz led police on a car chase, wrecked the car, and then shot Cpl. Nix when he could not get away.
“By your verdict today when you do justice, you are going to reaffirm for … all the other police officers in the city that it’s worth it,” Mr. Beach said. “It does matter.”