Richard "Gary" Black Jr., a 73-year-old Vietnam Army veteran, was shot and killed by an Aurora police officer in July while defending his son and grandson from an intruder, according to a District Attorney report. No charges will be filed against the officer.

AURORA — No criminal charges will be filed against the Aurora Police Department officer who shot and killed a homeowner defending his family from a home invader on July 30, according to a report released by the 17th Judicial District Attorney's Office on Monday.

The conclusion from the District Attorney's Office said the shooting was justified under Colorado law, as the officers on scene could reasonably have believed their lives were in danger.

Officer Drew Limbaugh fired several rounds at Richard "Gary" Black Jr. - a man Limbaugh did not know - in the early morning hours of July 30 during a night of chaos in the area of Montview Boulevard and Iola Street in northwest Aurora. Black had been walking toward officers from inside his house with a gun and flashlight, ignoring commands to drop the weapon, according to the DA report.

Officers had just heard the sound of gunshots come from deeper inside the house and were told by dispatch that someone was trying to drown a child inside. Those gunshots turned out to be Black shooting and killing an intruder that had been attacking his son and grandson in a bathroom, the report said.

Just 24 seconds passed from the time Black fired on the intruder and when police fired on Black. According to the report, Black raised a flashlight quickly toward officers, and that's when Limbaugh fired. There were three other officers on-scene, none of which could recall if they identified themselves as police officers to Black.

Late Monday night, Aurora police released a statement saying an internal investigation into the night would begin now that the District Attorney has opted not to file charges. APD also released a four-minute clip of body camera footage from the night showing the scene before, during and after Black is shot. WARNING: Due to the violent nature of the video, viewer discretion is advised.

The details of that chaotic night in Aurora

Calls began coming into dispatch just before 1:30 a.m. from people at a home near the site of the officer-involved shooting; according to the DA report, unidentified callers from the 1990 block of Iola Street warned dispatchers about an "altercation" and said that police needed to get on-scene quickly. Calls continued to come in about a disturbance and a man acting strangely. That man was later identified as Dajon Harper.

A woman called 911 about a bleeding man - also Harper - trying to break into her house, Black's house, on the 10000 block of Montview Boulevard, just down the street from the Iola 911 calls. The report notes the dispatcher could hear the sounds of banging and overlapping yelling in the background. A different woman then got on the phone and said Harper was on drugs and was her son.

According to the DA, Harper had just gotten out of prison and was celebrating a birthday with his family and friends not far from Montview Boulevard on Iola Street.

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The first woman's voice told the dispatcher Harper had broken down her door and that there was a whole other family in their living room, according to the DA. The dispatcher asked if there was a gun, to which the woman said she didn't think there was.

Four officers showed up only a few minutes after the 911 calls, the report says. By the time they got there, they were told over dispatch that "there are reports of a male trying to drown an 11-year-old."

The officers also saw blood on the sidewalk outside, a group of people in the driveway and a lot of noise, the report says.

Investigators combed through 94 body-worn camera videos from the night of the shooting. According to the body cam section of the report, a woman told Sgt. Patricio Serrant that someone was in her house and trying to drown her grandson. While the officers walk up to the house, a man suddenly appeared in the doorway with his hands raised. The man quickly told police he was just trying to help and that he wasn't "the guy" before leaving the house.

As the officers continued approaching the house, two gunshots were heard further inside. Officers Serrant and Limbaugh used their flashlights to illuminate the already lit living room of the house and see Black - in a bathrobe and carrying a gun - meandering slowly toward them from a hallway deeper in, the report says.

Officers shouted at Black to drop the gun, but he continued toward them and then quickly raised a flashlight in their direction, the report says. That's when Limbaugh fired his gun five times, hitting Black three times in his chest and back.

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Serrant yelled inside for anyone else to identify themselves, the report says. A child started yelling further in and a man - likely Black - said softly that his grandson and son were further in, in a bathroom, according to the body cam section of the report.

Later, as an officer was escorting the child out of the house wrapped in nothing but a bath towel, the child turned to Black on the floor and says, "That's my grandpa. He saved me," according to the report. In an interview a short while after that, the child told police officers that a man came into their house, dragged him into the shower and tried to rape and drown him before his grandpa came in and "beat his ass," the report says.

Serrant told investigators it wasn't until the child said the man on the ground was his grandfather did officers realize Black actually lived there, the report says.

In an interview with investigators, Limbaugh - the only officer that opened fire on Black - said he "felt like he had to the shoot at the man, because it was not an option to 'wait and see what happens.'" He told investigators he had no description of a suspect and had no idea who Black was at the time.

After the shooting, Black was rushed to a local hospital where he died from his injuries.

Harper, the man who'd invaded Black's house and was shot and killed by Black had a history of armed robbery and other crimes, the report says. He had methamphetamine and marijuana in his system the night of his death.

Black was a 73-year-old Vietnam Army veteran and recipient of the Bronze Star and Purple Heart, according to his half-brother.

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Aurora Police Department official statement

APD's Chief Metz released a statement just before 9 p.m. Monday night calling the situation that led up to Black's death "tragic" and said an internal investigation has begun into the matter.

Metz ran through the established details of the night in his statement and said that when officers opened fire on Black they had no idea he was the little boy's grandfather who'd just shot an intruder.

The chief said the Police Department and Black's family have agreed to release part of officers Limbaugh and Serrant's body camera footage, including footage that shows Black being shot three times and falling to the floor.

"The officer who shot Mr. Black currently remains in a non-enforcement role," he continued. "With the release of the DA's declination letter, an internal investigation will begin.

What the Black family thinks of the shooting

The Black family has hired an attorney in the months since their patriarch was killed in his own home. Qusair Mohamedbhai told 9NEWS the life of Black has since been "tarnished and sullied by our government and their efforts to protect a police officer.

He said he spoke to Black's surviving family and that they are devastated at the news no criminal action will be taken against Limbaugh. The family also considers the report an attempt to smear and tarnish a hero and veteran's deeds, Mohamedbhai continued.

He said the report released Monday by the DA is an attempt to "whitewash" what happened and that the family had hoped a jury would decide if charges needed to be brought up in the shooting - not a district attorney.

"Chief Metz has informed the community that no law enforcement identified themselves as police," Mohamedbhai told 9NEWS. "Shots were fired within seconds of police arriving... police were in darkness when they shot. Mr. Black took no aggressive efforts toward any police officer. The gun was down the entire time - these facts are not stated in the report."

Mohamedbhai would not commit to filing a civil lawsuit against the police department or any of the officers involved. He said the family looks forward to a "dialogue" with APD and that they want to make sure this kind of tragedy never happens again.

In a closing paragraph of the report, District Attorney Young admits the circumstances of what happened to Black invites a debate about police use of force.

A legal expert on the case

9NEWS legal analyst Scott Robinson agreed with Young's decision not to file charges, saying the officers were faced with an incredibly chaotic scene, and the case of an armed homeowner only makes things more complicated for officers.

"[Officers] have to make split-second decisions - life and death decisions," Robinson said. "Had the homeowner dropped the gun when police ordered him to do so - this wouldn't have happened." He added that one of the principal drawbacks of home protection is that the homeowner has to make absolutely sure the person holding the gun is not a police officer.

Robinson also pointed to the officers' alleged failure to identify themselves as police. He said it's not enough for responding officers to shout "drop your gun". The family claimed to the media in the days after the shooting that Black was hard of hearing, but Robinson said that would make little difference from a legal standpoint.

"The officers could not possibly know whether the individual they confronted did or did not have a hearing problem," Robinson said. "That's not something they'd even have a chance to think about in the heat of the moment."