PONTIAC, Mich. (Michigan News Source) – The mother of the convicted Oxford High School shooter wants three witnesses banned from testifying at her upcoming trial.

The Detroit Free Press reports that Jennifer Crumbley argues the eye witness accounts are “gruesome” and “appalling” and could unfairly prejudice the jury.

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The trials of Jennifer Crumbley and her husband, James Crumbley, are scheduled for Jan. 23. They each face four counts of involuntary manslaughter charges for their alleged roles in the murders of four students killed by their son.

Prosecutors allege the parents bought the gun for their son that he used in the crime and refused to get him mental health treatment, although court documents have challenged the validity of those requests.

Their son is spending life in prison without the possibility of parole.