Adams County Judge Terri Harder granted the motion for a second evaluation on Jan. 23 and scheduled it to be conducted at the end of February at the Nebraska Department of Corrections’ Reception and Treatment Center, where Mattison is being held.

Mattison faces charges of attempted second-degree murder, attempted first-degree assault on an officer, terroristic threats, use of a firearm to commit a felony, possession of a firearm by a prohibited person, and possession of methamphetamine.

Most details of the case haven’t been released as outside law enforcement agencies investigate the incident on Sept. 27, 2022, in the 300 block of South Lincoln Avenue. A judge sealed the arrest affidavit in the case.

Multiple HPD officers were involved, with two firing their weapons, but no injuries were reported, according to a news release from HPD.

Because HPD officers were involved in the incident, the South Central Area Law Enforcement Services (SCALES) has been asked to investigate. SCALES agencies include the Buffalo County Sheriff’s Department, Kearney Police Department, Grand Island Police Department and the Nebraska State Patrol. The Buffalo County Sheriff’s Department has been designated as the lead investigating agency.

Mattison was arrested for an outstanding warrant.

Mattison also faces a vehicle theft charge in Platte County and charges of operating a motor vehicle to avoid arrest and driving under suspension in Hall County.