By KNEZ WALKER, CANDACE SMITH, IGNACIO TORRES, DEBORAH KIM, ALLIE YANG, and ANTHONY RIVAS, ABC NEWS

(AURORA, Colo.) — Sheneen McClain’s 23-year-old son, Elijah McClain, died nearly a year ago in Aurora, Colorado, just a few days after police confronted him as he was walking home from a convenience store.

“I honestly don’t think my anger or … me being upset is gonna change,” she told ABC News. “I think I’m always going to have that same level of being pissed off.”

Elijah McClain’s family says the conflict involved a deadly use of excessive force. The police called it justified. His case was closed and the police officers involved were allowed to return to work.

Now, in the wake of George Floyd’s death, protests have filled the streets and Elijah McClain’s case has been given new attention, including in his home state.

“It hurts because I honestly didn’t understand why Colorado wasn’t there for Elijah like they were for George Floyd or even Breonna Taylor,” Sheneen McClain said. “Everybody’s screaming names now, but … last year it would have made a big difference.”

Now, it’s her son’s name chanted at marches across the country, from Denver to New York City. Thousands of people have taken to the streets, fueled by online campaigns and petitions, highlighting case after case of Black Americans killed by police and a lack of accountability.

“The George Floyd case was a game changer,” Marc Lamont Hill, a media studies professor, author and activist, told “Nightline.” “That opened up the door for questioning all sorts of stuff when it comes to law enforcement.”

This week, thousands of protesters filled the streets of Colorado. One group shut down a busy highway in Denver. At one point, Aurora police dressed in riot gear, dispersing crowds using pepper spray and tear gas to break up a peaceful vigil in McClain’s hometown.

“The fact that it always takes a public struggle in order to get an arrest and an indictment and a prosecution speaks to the failure of the system to provide swift justice, and for many people, justice delayed is, in fact, justice denied,” Hill added.

Sheneen McClain says her son was always introverted. She said he’d channel his shy nature by expressing himself through art.

“As an introvert you have to find different ways of communication,” she said. “He loved knowledge… That’s how he taught himself how to play the instruments — the violin.”

“It was interesting when he started because I was like, ‘How are you gonna play all these instruments at one time?’ And he’s like, ‘I’m gonna do it,’” she added. “So, we watched and he did… It was amazing to see him so enchanted with his own skill, and we were all enchanted, too. So, yeah, pretty amazing.”

By last year, Elijah McClain had been working as a massage therapist for several years and he had plans to go to college.

On the night of Aug. 24, 2019 around 10 p.m., Elijah McClain went to a convenience store near his home to buy some soft drinks. In surveillance video from the store, he can be seen wearing a ski mask. His family says he was wearing it because he had anemia, a blood condition that can make people feel cold more easily, and the mask kept him warm.

While McClain was making his trip to the store, someone had called 911 to report a suspicious person. Referring to McClain, the caller described him wearing a mask said he looked “sketchy” but added that “he might be a good person or a bad person.” When asked, the caller told the operator that there were no weapons and that no one was in danger. The operator advised him that officers were on their way to check it out.

When officers Nathan Woodyard, Jason Rosenblatt and Randy Roedema stopped Elijah McClain on his way home, one telling him that he was “being suspicious,” according to police body camera video. McClain responded, “I have a right to go where I am going.”

The officers immediately grabbed McClain, who repeatedly told them to let him go.

“I am an introvert. Please respect the boundaries that I am speaking,” McClain pleaded. “I’m going home… Leave me alone. You guys started to arrest me, and I was stopping my music to listen.”

“This is a small kid … small in height, small in build. Somebody who probably could have been detained by one officer and certainly didn’t require three officers, a chokehold and a sedative,” Hill said. “And the fact that we can’t see all of it on camera because they say that the camera dropped is also a big red flag.”

Two of the three officers’ body cameras became dislodged within seconds and fell to the ground. The third camera captured a little more of the struggle before it fell, too.

“There was absolutely no reason legally why the officers should have stopped him in the first place,” Mari Newman, a lawyer for the McClain family, told ABC News.

“When he said ‘I’m just going home. I’m just going home. I’m an introvert. Please respect my boundaries,’ they grabbed him. They tackled him. And they threw him to the ground,” she said.

As police tried to apprehend McClain, he offered them his ID, gave them his name and told them he was just going home.

Two minutes into the video, Elijah McClain could be heard repeatedly saying, “I can’t breathe” — a phrase that has become a national rallying cry. He told officers he was in pain. One of the officers could be heard saying in the video that they were using a “carotid,” a type of chokehold that restricts the carotid artery, cutting off blood to the brain.

As McClain was pleading with the officers, one of them could be heard justifying the takedown by saying he was wearing a mask. He also said that he saw Elijah McClain reach for one of their guns.

As more officers arrived, the original three looked around for their body cameras. They picked them up and repositioned them — one was turned off.

Mari Newman and the McClain family believe the lack of clear body camera footage was on purpose.

“All three of those officers intentionally dislodged their body cameras,” she said, pointing to a part on one officer’s recording where one officer who is holding down McClain tells another officer to move his camera.

In the video, the officer can be heard seen and heard saying, “Move your camera, dude.”

Newman says, “So, he’s intentionally trying to stay off of the body camera as they inflict multiple different kinds of force on Elijah McClain.”

During this time, multiple officers are holding McClain on the ground. At one point, the 23-year-old gets sick and vomits. When EMTs arrived, they gave him at shot of 500 milligrams of ketamine, a sedative. Soon after, McClain was loaded into the ambulance, where he had a heart attack.

Once at the hospital, Sheneen McClain said “it took so long for [the police] to just be honest with me.”

She photographed her son’s physical injuries while he was on life support. Eventually, doctors declared him brain dead and, three days later, he was taken off life support.

“Bone of my bone, flesh of my flesh. That was a part of me. There’s no way to put a band-aid on that, he’s always gonna be gone,” she said. “He’s gone. All this should have been done before he was killed. Those laws that allowed them to even go that far should’ve never been in place.”

The investigation into Elijah McClain’s death was taken up by District Attorney Dave Young. He said that when he first saw the videos, his “initial impression” was that the ketamine caused Elijah McClain’s death.

“It wasn’t until I received the forensic autopsy report that I learned that, in fact, was not the cause of death,” Young told ABC News. “In fact, we don’t know the cause of McClain’s death.”

Young said he could not “prove one way or the other” if the police officers’ actions led to Elijah McClain’s death.

He said “I don’t know” whether the officer’s actions led to McClain’s death.

“The burden of proof is on me,” Young said. “If I can’t prove to a jury of 12 that there’s actions cost his death then I cannot file criminal charges.”

In November, the district attorney announced they would not bring charges against the officers, who had been placed on administrative duty during the investigation.

“I don’t condone the officers’ actions out there,” Young said. “In fact, I wish they would have done things differently. But I cannot… If someone’s saying they can’t breathe, get off of him. Do it, just get off of him!”

Hill points out there’s a history of white men with weapons getting taken into custody without violence – even in the same city Elijah McClain died.

“Look at James Holmes, a white man who was a mass murderer, was able to be arrested without incident,” Hill said of the murderer who shot and killed 12 people at a movie theatre in Aurora, Colorado in 2012. “Somehow, when it comes to white suspects, police managed to locate a level of discipline and care and patience that they don’t for black suspects, even ones who were unarmed.”

In addition to calls for justice for George Floyd and Breonna Taylor, the protests that have emerged around the country have been calling for accountability in older cases as well. There are currently several petitions demanding that Young resign, including one that’s accrued 50,000 signatures.

“Now, I’m not going to consider doing that,” Young said. ““I stand by my decision. It’s unfortunate that people feel that by voicing their opinions that that’s going to change the facts and the law of the investigation.”

Still, the public pressure has sparked action. Colorado passed a police reform bill earlier this month with new accountability measures for officer-involved killings. Last Thursday, Colorado Governor Jared Polis appointed the state’s Attorney General Phil Weiser as special prosecutor to investigate Elijah McClain’s death and potentially file charges.

“The fact that a special prosecutor is being appointed and they’re still looking into this, both formally and informally suggests that public outcry matters,” Hill said. “When people pay attention and hold institutions accountable, those institutions will respond differently than if nobody is watching.”

All three officers, Woodyard, Rosenblatt and Roedema have been taken off enforcement duties and reassigned. Sheneen McClain believes they should spend life in prison.

“Justice to me … is conviction. … Like, they need to suffer. Life in prison would be great for me. Honestly, they need to be convicted for what they did because it was unjust,” she said.

McClain now realizes that Elijah has become much more than just her son, he’s become a symbol.

“We’re gonna keep saying’ his name,” she said. “We’re gonna shout it even louder every day, All lives can’t matter if Black lives don’t matter. The revolution is now. Ain’t no more waiting’ for it.”

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