DONIPHAN, Mo. -- A judge found a man accused in the shooting death of his father to be mentally incompetent to stand trial.

Bryan Portwood Jr. is not currently capable of assisting in his own defense, according to a ruling from Judge Thomas Swindle, made Tuesday morning in Ripley County's temporary courtroom at Doniphan City Hall.

Portwood has been held at Fulton State Hospital since shortly after his arrest in November on suspicion of first-degree murder in the shooting death of his father, first-degree assault in the shooting of his stepmother, unlawful use of a weapon and two counts of armed criminal action.

"He will be committed to the Department of Mental Health until such time as he is competent to stand trial," said Ripley County Prosecuting Attorney Chris Miller. "The criminal case has been suspended."

Miller said he will not challenge the determination, which is based on a long-awaited written report from a doctor who completed a mental evaluation of the 22-year-old.

"Based on information I have had about the defendant for some time, I have no intention of trying to find another psychologist to offer a different opinion," Miller said. "I am not confident that would be achievable, and it would be expensive and time-consuming."

Miller said he could not comment on the report that led to the judge's ruling or why doctors say Portwood is mentally incompetent.

Portwood will be re-evaluated in six months and periodically after that, Miller said.

"The judge has asked for further evaluations to see if there is improvement," Miller said. "If there is, the prosecution will be resumed."

Should no progress be made, the judge would have to determine if it is likely Portwood's condition will improve.

Authorities allege Portwood shot and killed his father, Bryan Portwood Sr., on Nov. 2 at the family's Doniphan home. Portwood is accused of then shooting his stepmother, Jeana Portwood. She recovered from her wounds.

Officials said at the time Portwood Jr. might have mental health problems and that this had not been their first call to the family home.

The man was found mentally incompetent in a civil setting according to Missouri's Case.net. Guardianship was given to Ripley County public administrator Brenda Thompson five days after Portwood Sr. was killed, court records say.