KALISPELL (AP) - Jesse Ernst turned himself in Thursday and was transported to the state hospital at Warm Springs.
Ernst, 21, said he was "being cooperative or whatever the word is."
Ernst was found innocent of murder and burglaries by reason of mental disease or defect last month during a retrial. Earlier this week, he was placed under supervision of the state Health and Human Services Department.
Ernst, 21, was charged in the 1997 murder of Bigfork businessman Larry Streeter. His brother, Ted, is serving a 100-year prison sentence for the murder.
Ernst was accompanied by his sister, Cari, his grandmother and two supporters.
His attorney, Phyllis Quatman, immediately filed motions to stop Ernst's commitment and seeking a rehearing on grounds Ernst's civil rights are being violated.
Quatman objects because the mental-health expert hired by the court to evaluate Ernst recommended against placing him in prison or an inpatient psychiatric treatment center.
Ernst said he was "a little bit confused" and nervous about his situation.
Officials said Ernst will be housed in the criminal ward of the state hospital.
Within 180 days, the hospital plans to file a report with the court about what it believes Ernst needs for treatment and placement.
"In this case, we may do that sooner," said Ed Amberg, hospital administrator.
The court gave the state agency discretion in what it does with Ernst.
The court order committing him to the department's care doesn't specify that he stay at Warm Springs, and placement outside the hospital may be an option, Amberg said.
Ernst's stay is considered indefinite until evaluations are complete. Criminal patients at the hospital are evaluated annually.
Typically, if a patient is found to be no longer dangerous and to be free of mental illness, a court makes the decision to discharge him or her, Amberg said.