SACRAMENTO, Calif. — The teen accused of killing high school football player Jaulon "JJ" Clavo in 2015 was found guilty Monday.

Keymontae Lindsey, 19, faced three charges: first-degree murder with a firearm, first-degree attempted murder with a firearm and firing a firearm into an occupied motor vehicle. In court Monday afternoon, Sacramento Superior Court Judge Michael Sweet declared he'd found Lindsey guilty on all three counts.

On November 13, 2015, Clavo, 17, was driving himself and several of his football teammates back to Grant High School after they got food between the end of the school day and a playoff game. It was while they were driving back to campus that Clavo was shot and killed. One of his passengers, fellow teammate Malik Johnson, was injured by the gunfire. Altogether, five rounds of ammunition were fired, Judge Sweet recounted in court Monday. Two shots hit Clavo.

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Lindsey was arrested the day after Clavo's death when a weapon was found at his feet during a traffic stop. Initially, he was booked into juvenile hall on a weapon charge. An investigation later found Lindsey's gun was connected to Clavo's shooting, according to Sacramento Police.

JJ Clavo's mother Nicole Clavo was at Monday's hearing.

She describes her son as "a funny, cute, handsome jokester. Loved football. Loved people. Just loved life."

Lindsey was 15 at the time of the crime and is now 19. He has bounced back and forth between adult and juvenile court due to Senate Bill 1391, which became effective Jan. 1, 2019 and bars minors under the age of 16 to be tried as adults in California.

"I truly don't know how to define justice in my world," Clavo told ABC10 after the judge declared Lindsey guilty. "Yes, he was found guilty of all three, but yet he was 15 at the time of the crime. He was a baby, he was a kid. I don't think we should even be here.”

She said she felt numb after the hearing, that the system is broken and that a teen shouldn't have had been able to commit this crime in the first place.

"In saying that," Clavo continued, "I have fought for him to be tried as an adult. I do not believe that he should get off of all the charges he's facing and only have to do a limited amount of time. I don't think our system is created to truly rehabilitate in the short amount of time he will serve."

Lindsey's sentencing is set for 1:30 p.m. on Mon., August 19. The judge added a gang enhancement that could increase his punishment. Judge Sweet said evidence points to a gang rivalry, existing between the Del Paso Heights Bloods and the Strawberry Manor Bloods. He said Lindsey was active with the Strawberry Manor gang and that he was targeting Clavo's passenger, Malik Johnson, who wasn't a member of the rival gang at the time but has since become one, the judge said the evidence shows.

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Even though Lindsey was aiming for Johnson, the judge said, the legal doctrine of transferred intent says it doesn't matter that he missed his target and killed Clavo instead; the premeditation for Johnson's killing transfers over to Clavo.

His mother, Ranika Lindsey, told ABC10 she thinks the judge made an incorrect ruling, "but it is what it is."

Prior to Monday's hearing, Lindsey and Clavo embraced and prayed together. These mothers who are both grieving, whose lives were both irrevocably changed that Nov. 2015 day, came together in their sadness to share some of the heaviness of the day.

Since the death of her son, Clavo has become an advocate for preventing gun violence. ABC10 asked her about the recent string of mass shootings.

"It's been a sad week, right? Gilroy, Ohio, El Paso. There's so many families suffering and they don't even know what they're headed through in the emotions," Clavo said. "I just continue to pray for them and lift them up and send them strength and love."

She said losing a loved one and the events following that are stressful and tiresome.

"Gun violence-- I don't know what the answer is, but I know that we need to be at the table, as victims, in having a say," Clavo said.

She doesn't feel she and other victims were heard in their protest of SB1391.

"That wasn't a bill put forth for victims. It wasn't a bill put forth for communities. It wasn't a bill put forth for those who support victims. It was truly a bill that only helped those who perpetrated or committed a crime," Clavo said.

Even at 15, she said, a young person can understand what they're doing when taking another person's life.

"He knew what he was doing, and he should be facing the crime that he did," Clavo said. "If he would've been tried as an adult, he'd be doing life - with possibility of parole, but he'd be doing life, and I'd be sitting at every hearing. Now we're putting this in the hands of the DJJ - juvenile department, and he'll be out before he's 25. Where's the justice in that?"

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