By CBS13 Staff

MODESTO (CBS13) – On Friday, the family of Trevor Seever, an unarmed man shot and killed by Modesto police in December, called for more serious charges to be filed against the former-officer who pulled the trigger.

The Modesto Police Department on Thursday announced the firing of Officer Joseph Lamantia after investigators determined the use of deadly force was in violation of the department’s policies.

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Lamantia was arraigned Thursday afternoon for felony voluntary manslaughter. The Seever family issued a press release on Friday calling for more.

“While the family is grateful that Officer Lamantia is being criminally prosecuted, the family nonetheless feels that Officer Lamantia should face the more serious charge of murder, rather than the less-severe charge of voluntary manslaughter,” the press release said.

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Lamantia shot Seever several times on December 29. Modesto police said officers were called to the 2300 block of Woodland Avenue near The Church of Brethren after receiving a call from Allison Seever, Trevor’s sister, who said her brother bought a gun and was making threats. A gun was not located at the scene.

“It is a difficult time for a family who supports law enforcement but who lost a son and brother due to an unjustified and avoidable fatal shooting,” the family said. “The family recognizes and appreciates the role that law enforcement plays in protecting our community, but the unfortunate circumstances leading to Trevor’s wrongful death highlight the serious need for reform and accountability.”

Lamantia entered a not guilty plea in court Thursday. Judge Jeffrey Mangar ordered him to remain in custody and his bail was set at $100,000. According to the Stanislaus County Sheriff’s office, Lamantia was booked in jail around 1:40 p.m. and released. He is due back in court on June 17.

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“Yesterday’s actions won’t bring Trevor back,” the family said. “However, they should help family members and the Modesto community begin the important first steps toward improving relations between our Police Department and our community, holding the City and law enforcement accountable for their actions, and making Modesto a better place to live. Justice for Trevor!”