COEUR d’ALENE — Prosecutors and an expert defense witness who took the stand for six hours Thursday clashed over scientific evidence that the state called questionable, but the defense used to show Jonathan D. Renfro suffers from brain abnormalities.

The evidence was used by the defense to enforce earlier expert testimony that Renfro’s dysfunctions played a significant role in the defendant’s shooting Coeur d’Alene Police Sgt. Greg Moore to death two years ago.

Renfro, 29, who was convicted earlier of murdering Moore, could receive the death penalty if jurors after considering evidence rendered in this final phase of his trial that began Sept. 11, agree that it is warranted.

Earlier this week in Coeur d’Alene’s First District Court, Dr. Mark Cunningham, a Seattle clinical forensic psychologist hired by Renfro’s attorneys, for two days listed for the jury an array of adverse or impairing factors that disposed the defendant to a life of crime, that culminated in the May 2015 fatal shooting of Moore.

Cunningham argued that the defendant’s hyperactivity and recklessness brought on by ADHD, parental neglect, coupled with a series of head injuries, a history of alcohol abuse among relatives and his own drug and alcohol abuse from an early age, lousy peers, serial impulsivity and learning disorders were symptomatic of neurological dysfunction.

Deputy prosecutor David Robins boiled it down to something else.

“Did he have a choice?” Robins repeatedly asked.

Renfro did make a choice when he shot Moore, Cunningham said.

“The point of this is not that he had a choice,” he said. “But what’s been loaded into his system, what’s he’s making the choices with.”

Thursday’s expert witness, forensic psychiatrist Richard Adler, further developed the argument that Renfro suffered from a brain disorder evidenced by a series of photograph-like images of Renfro’s brain that showed points of trauma. He pointed out degeneration of white matter responsible for transmitting information from the front to the back of the brain, and shrunken portions on one side of the brain that were not symmetrical with their mirror images on the other side.

Physical evidence coinciding with the findings include Renfro’s choppy speech patterns and mannerisms as well inabilities to make cognitive connections, and his lack of social skills, Adler said.

Defense attorney Jay Logsdon asked if the images were obtained through a discredited method, one that has “been attacked as junk science?”

The method, called QEEG, for quantitative electroencephalogram, which uses electrical patterns that show electrical activity inside the brain’s cortex to determine impairment, was attacked in an article in 1997. The article’s criticism still stands today, Adler said.

Throughout the morning and into the afternoon, Adler reiterated findings, linking them to the defendant’s actions, and dovetailing them into other test results, psychological and cognitive, that have been conducted while Renfro has been incarcerated in the Kootenai County Jail.

Since Renfro has been prescribed Seroquel, an antipsychotic medicine often used to treat bipolar and depressive disorders, many of the symptoms have been relieved, and the defendant experiences something closer to normal brain functioning, Adler said.

But, just because he is now on medication that seems to alleviate anger and irritability, Robins said, doesn’t mean Renfro - who has a history of resistance to taking prescribed medications - will continue to take the meds in prison.

It doesn’t mean that the convicted murderer will act nicely, he said.

“Are you aware Mr. Renfro has a history of being medically non-compliant while incarcerated?” Robins asked. “He cheeks his pills. He doesn’t take them; he hoards his medication.”

Robins scrutinized Adler’s representation of the QEEG results.

Renfro can still make his own choices, Robins said.

“Certainly. Yes,” Adler replied.

He was not delusional or suffering from schizophrenia.

“No, he is not schizophrenic.”

He was not psychotic, Robbins inquired. He knew he was shooting a police officer, correct?

“I have no idea,” Adler replied.

Three other physicians who performed MRIs on Renfro found no evidence of the brain disorders that Adler described using data from the QEEG, Robins said.

“In essence, his brain looked normal,” Robins said.

The results of MRIs are determined by their outward interpretation and they are not as sensitive as a QEEG, which measure brain waves, Adler said.

Robins read through a series of test results that Adler agreed were normal, but didn’t represent the whole picture.

“The nature of the brain is if you have areas malfunctioning, you are in trouble,” Adler said.

Some of Renfro’s behavioral patterns, documented in the findings, were outside the norm, Adler said.

“He wasn’t barking like a dog,” Adler said. “It wasn’t grossly bizarre behavior. It was something outside the norm.”

As a psychiatrist, the behavior is something that is easily spotted,

“If you see it, you know it,” he said.

Before excusing the witness, Robins returned to the question of choice.

Renfro, when he confronted Moore, had a choice to flee or pull the trigger, he said.

Adler, as Cunningham had stated in earlier, said choices are based on wiring.

“When you make a choice your ability may be impaired,” he said. “If you have an impaired nature, the nature of your choices are not the same as a normally constituted person.”

The final phase of the trial to determine if Renfro should be put to death resumes today at 9 a.m.

in Courtroom 1 of the Old Kootenai County Courthouse.