(CNN) New body camera footage captures the tense moments before an Arizona police officer shot an unarmed man dead last year, as the man begged officers not to fire.

Police in Mesa, Arizona released the footage last week, after a jury acquitted former Mesa officer Philip "Mitch" Brailsford of second-degree murder and reckless manslaughter charges related to the January 2016 shooting of Daniel Shaver, of Texas.

Brailsford shot Shaver after police responded to a call saying a man was pointing a rifle out of the window of a La Quinta Inn. The former officer testified he believed Shaver was reaching for a gun in his waistband as he moved toward officers, CNN affiliate KTRK/KPHO reported. No weapon was found.

An attorney for Shaver's widow said the footage shows the shooting was unjustified, while Brailsford's lawyer said his client's actions were consistent with his police training.

"That's an execution, pure and simple. The Justice system miserably failed Daniel and his family," Mark Geragos, the attorney for Shaver's widow, Laney Sweet, said in a statement.

In an interview last week with CNN, Brailsford's attorney, Mike Piccarreta, said jurors heard six weeks of testimony and watched the body camera footage several times before acquitting the former officer.

"While it's a compete tragedy, he's comforted by the fact that his response was in view with the way he was trained," Piccarreta said.

Daniel Shaver, left, and ex-Mesa officer Philip Brailsford.

The graphic footage prompted anger on social media.

Black Lives Matter activist DeRay Mckesson tweeted: "I keep thinking about how effortlessly that police officer killed #DanielShaver in that hotel hallway. And how the officer was acquitted. The only person to fear in that entire situation was the officer himself."

We talk about the disproportionate violence of the police towards people of color because it's true. It's also true that the police kill white citizens too. Police violence is everyone's problem. #DanielShaver should be alive. — deray (@deray) December 11, 2017

"God bless #DanielShaver," director and producer Ava DuVernay tweeted.

'Please, don't shoot me'

When police arrived at La Quinta, they ordered Shaver and a woman to come out of a room on the fifth floor, KTRK/KPHO reported.

The body camera footage shows Shaver on his knees in the hotel hallway, a few feet away from the barrel of a police officer's gun.

"Hands up in the air," an officer says.

Shaver puts his hands on the floor, then behind his back, then moves them forward again before an officer yells "Hands up in the air!" Shaver moves his hands up above his head.

"You do that again, we're shooting you, do you understand?" the officer said.

"Please, do not shoot me," Shaver said.

"Then listen to my instructions," the officer said.

"I'm trying to just do what you say," Shaver said.

"Do not put your hands down for any reason!" the officer later says to Shaver. "You think you're going to fall, you better fall on your face. Your hands go back in the small of your back or down, we are going to shoot you! Do you understand me?"

"Yes, sir," Shaver says, sobbing.

An officer then orders Shaver to crawl toward him. As Shaver crawls, he appears to reach behind him with his right hand.

That's when Brailsford fired five rounds, killing him.

After the shooting, several witnesses and hotel employees told police Shaver was drunk. An autopsy revealed Shaver's blood alcohol level was .29, more than three times the local definition of intoxication, KTRK/KPHO reported.

Witnesses later told police Shaver was showing them an air rifle he had used in his job as a pest exterminator.

Brailsford was fired because of the pending second-degree murder charge and for having the words You're F***** engraved on a part of his personal, department-approved AR-15, Mesa police spokeswoman Sgt. Diana Williams told CNN.

Ben Meiselas, an attorney with Geragos' firm, confirmed that the AR-15 that Brailsford used in the shooting had an expletive etched into it. But the judge did not allow the AR-15 into evidence because he ruled it "too prejudicial" and "not sufficiently relevant," he told CNN.

Brailsford had worked for the department for two years, KTRK/KPHO reported.

During the trial, Brailsford told jurors he was trained to deal with a threat.

"I was doing what I needed to do to protect my fellow men and the woman we had just taken into custody," Brailsford testified, according to CNN affiliate KTRK/KPHO

Brailsford testified Shaver disobeyed orders not to put his hands behind him on several occasions, the station reported.

"For some reason, he placed his hands behind his back," Brailsford said. "For one, I don't know why he did that."

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