It was the latest in a spate of killings that have prompted criminal charges against law enforcement officials.
Philip Brailsford, who shot and killed Daniel Shaver in the hallway of a hotel in January 2016, was acquitted of second-degree murder as well as reckless manslaughter by a jury on Thursday, according to USA Today.
Bodycam footage made public following the verdict showed Shaver, a married 26-year-old father of two, on his knees complying with the officers' instructions over the course of several minutes and saying "Please don't shoot me" and "Please don't shoot."
Shaver, who was inebriated, then appeared to reach to his back, possibly to pull up his shorts, before Brailsford fired five bullets at him with his AR-15 assault rifle.
Unlike several other high-profile cases in which African Americans were killed by police, both the police officer and Shaver were white.
A police report cited by local media said officers were responding to a report of a man seen holding a gun from his fifth floor hotel room.
Officers arrived at Shaver's hotel room in the Mesa suburb of Phoenix and found him with a woman, whom his widow Laney Sweet later said was visiting with a male colleague who had stepped outside to call his wife.
The local police department defended Brailsford's actions, saying he had acted in accordance with his training.
But Mark Geragos, Sweet's lawyer, described the killing as an "execution," according to local news outlet AZcentral. "The justice system miserably failed Daniel (Shaver) and his family," Geragos said.
According to USA Today, the judge did not allow jurors to hear that Brailsford had etched the words "You're F***ed" onto his service weapon because it could be prejudicial.
The verdict came the same day as former policeman Michael Slager was sentenced to 20 years for the killing of an unarmed black motorist Walter Scott -- a rare conviction in a judicial system rights activists complain often allows police to operate with impunity.
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