Wall's attorney has alleged that police badgered, intimidated and manipulated his client into making incriminating statements under duress.
Prosecutors, who filed a written response motion last week, claim Wall was level-headed and calm during the three-hour interview, during which he was given breaks, water and a magazine to pass the time while detectives were out of the room. He was not handcuffed. The interview room was not locked. He was read his rights.
"The interview was, for the vast majority of the time, held in a calm, rational, conversational tone," wrote Salt Lake County prosecutor Matt Janzen. "Detectives elevated their voices only at the last part of the interview lasting 6 minutes the first time and 1 minute the second time. There were no threats made. There were no promises of either more severe punishment or greater leniency if he confessed. None of these factors led to a coercive environment."
For months, Wall's attorneys have been trying to get the court to suppress everything the former pediatrician said to detectives on Sept. 27, 2011 just hours after Wall's ex-wife, Uta von Schwedler's body was found inside her Salt Lake City home.
Wall's interrogation lasted from about 11:30 that night until about 2:20 a.m., according to prosecutors. Defense attorney G. Fred Metos has said the exchange between Wall and the investigators "grew very heated," and Wall, among other things, discussed being diagnosed with depression and self-medicating with Lexapro and Trazodone.
He was emotional, frightened and confused, Metos has argued.
He also was duped by detectives into repeating the ideas they planted in his mind, Metos said that Wall was a monster, a killer.
Wall, 50, is charged with first-degree felony charges of murder and aggravated burglary. He has pleaded not guilty.
Third District Judge Denise Lindberg will issue a written ruling on the question of the police interview by early September. Judge James Blanch will preside over Wall's trial early next year.
When the 2011 interrogation ended, court documents claim, police dropped Wall off near his home and told him to walk the rest of the way.
When Wall arrived home, he was distraught, witnesses testified at an October preliminary hearing. He told his children that their mother was dead and the police believed he did it. Later, the mother of one of his children's friends came to the home and found him lying on the bed. Court documents quote Wall as telling the woman that "only a monster would do these things" and that he didn't know if he had killed von Schwedler.
Wall's attorney also seeks to suppress the statements Wall made at his home after the interrogation.
Wall was charged in April 2013, more than a year and a half after von Schwedler's death.
At an the preliminary hearing, a medical examiner testified that the case wasn't clear: the wounds von Schwedler suffered may have been caused by another person making this case a homicide or, they may have been caused by herself in a suicide.
The 49-year-old University of Utah scientist had cuts on her left wrist and leg and an injury to her throat, as well as a potentially lethal dose of the anti-anxiety medication Xanax in her system. She did not have a prescription for the drug.
She was found still and not breathing in her bathtub. A photo album of her children and a knife sat in the tub nearby.
But prosecutors insist Wall wanted von Schwedler out of his way documents allege Wall told various people that his ex-wife was "to blame for his problems."
Police noted that Wall had a cut on his face the night von Schwedler died, but he told detectives that a dog had scratched him.
The couple's teenage son, Pelle Wall, has described his father as dangerous and said he would fear for his safety if Wall were to be released.
Von Schwedler and John Wall had a heated and contentious divorce in 2006 that led to years of custody battles over their four children. Prosecutors point to statements Wall allegedly made to friends "it would be all right if Uta wasn't around anymore" as a motive for murder.
But Metos has said that Wall had been prevailing in the custody struggle.
Wall is expected to appear in court again in August before Judge Lindberg makes her final ruling in the question of his police interview.
In June 2013, Wall signed an agreement with the Division of Occupational and Professional Licensing, giving up his medical license and his ability to write prescriptions until the murder case is resolved.