By DeJanay Booth

(CBS DETROIT) — The family of one of the students killed in a mass shooting at Oxford High School is filing a new federal lawsuit.

Justin Shilling, 17, was one of four students who was killed on Nov. 30. Shilling’s family attorney Ven Johnson says school employees ignored a suicide prevention policy.

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Johnson claims school staff failed to check the alleged shooter’s property for weapons after finding alarming notes depicting murder. Johnson believes gross negligence on the part of Oxford High School employees disqualifies them from being protected by governmental immunity.

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According to a report from the Detroit Free Press, the parents of Tate Myre, who was also killed, as well as the parents of four surviving students also joined the lawsuit.

Myre was also killed in the shooting, as well as Madisyn Baldwin and Hana St. Juliana. Six other students and a teacher were injured.

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