OKLAHOMA CITY (AP) — An Oklahoma judge ruled Thursday that a death row inmate is Grayson  Prestonnot competent to be executed for his role in the 1999 slayings of a mother and son.

Pittsburg County Judge Michael Hogan issued an order in the case involving 61-year-old James Ryder in that county.

“The court could go on ad nauseum discussing the irrational thought processes of Mr. Ryder, but this is not needed,” Hogan wrote in his order. “To be clear, the court finds by a preponderance of the evidence, Mr. Ryder is not competent to be executed” under state law.

Hogan’s decision followed a competency hearing this week in which two experts for Ryder’s defense testified that he suffers from a psychotic disorder diagnosed as schizophrenia.

“James has suffered from schizophrenia for nearly 40 years and has little connection to objective reality,” Ryder’s attorney, Emma Rolls, said in an email to The Associated Press. “His condition has deteriorated significantly over the years and will only continue to worsen.

“As the court concluded, executing James would be unconstitutional. We urge the State to cease any further efforts to execute him,” Rolls continued.

Under Oklahoma law, an inmate is mentally incompetent to be executed if they are unable to have a rational understanding of the reason they are being executed or that their execution is imminent.

An expert for the state testified he believes Ryder is competent to sufficiently and rationally understand why he is being executed and that this execution is imminent.

Ryder was sentenced to die for the 1999 beating death of Daisy Hallum, 70, and to life without parole for the shotgun slaying of her son, Sam Hallum, 38.

Court records show Ryder lived on the Hallum’s property in Pittsburg County for several months in 1998 and took care of their home and horses when they were out of town. He had a dispute with the family over some of his property after he had moved out.

Under state law, the Department of Corrections and the Department of Mental Health and Substance Abuse Services are now tasked with determining the best place for Ryder to be held in safe confinement until his competency is restored.

“Attorney General Drummond respects the court’s decision, but is disappointed that James Ryder is now ineligible to be executed for the horrific slaying of Daisy Hallum and her son, Sam Hallum,” Drummond spokesperson Phil Bacharach said in a statement. “The state will continue working to restore competency so justice can be served.”