WALNUT CREEK (CBS SF) — The family of a Richmond murder victim voiced their outrage Thursday over a new state law that bars adult charges being filed against suspects 16 years old or younger in homicide cases.

Alexandrea “Allie” Sweitzer was killed on May 18, 2017 in Richmond’s Booker T. Anderson Park during a dispute over a bag of marijuana. Vincent Lising-Campos, who was 15 at the time of the shooting, was charged with murder in the case.

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Under the new state law signed by former Gov. Jerry Brown, Lising-Campos will not face a prison sentence and instead will be transferred into the juvenile system.

He pleaded guilty on Thursday to murder, 2nd degree robbery and 1st degree residential robbery. He may be eligible for release from the juvenile system by the time he turns 25.

Sweitzer’s mother, Melanie, was joined by other family members and friends in a protest Thursday morning outside a Walnut Creek courthouse where Lising-Campos was scheduled to make his plea in the case.

“The Contra Costa District Attorney has decided that she is not going to let her office fight for our daughter to the fullest extent that we should be allowed,” Melanie Sweitzer told KPIX 5.

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She said the prosecutor on the case does not agree with the decision.

“We went through a year of hearings where he (Lising-Campos) was found unfit for the juvenile justice system,” Sweitzer claimed. “He could not be reformed in the juvenile justice system so they sent him to adult court… (Now) he’s never going to be sentenced (to jail). He’s going to be deemed a juvenile delinquent.”

Sweitzer added that this was not the only violent crime the teen defendant was accused of committing.

“He didn’t just murder my daughter. Just a couple days before that, he went into someone’s garage and robbed him and shot him. OK, he didn’t die, but he’s still shooting people. Two days before killing my daughter,”

Contra Costa County District Attorney Diana Becton issued a statement earlier this week about the case.

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The statement read in part, “Senate Bill 1391 is the law in the State of California. My decision cannot and does not rest on the facts of one case. Let me be clear, this decision in no way undermines the rights of victims or their families.”