"I want to make it very clear that our only interest in this case is truth," Grunander told Judge Samuel McVey, who declined to rule on the motion so prosecutors can respond in writing.
Grunander said the case file including all the documents at issue has been available to defense attorneys at his office. He said he has invited the two attorneys to come there on several occasions to discuss the case, but has never received a response.
"They're explosive allegations ... ," Grunander said outside of the courtroom. "We don't have anything to hide here, I want to be very, very clear about that."
According to the defense attorneys' filing, they obtained a thumb drive from one of the prosecution's expert witnesses, Dr. Joshua Perper. On the thumb drive were a number of "explosive" documents they claim were not disclosed during the discovery process, the attorneys wrote.
The thumb drivecontained a letter from the Utah County Attorney's Office which is investigating the case addressed to the New York law school of MacNeill's son, Damian MacNeill, advising school officials that Damian could be potentially dangerous to students, staff and others, according to the defense.
"Investigators in the Utah County Attorney's Office deemed him to be a very dangerous individual who possessed homicidal impulses and discussed the 'joys of killing,' " the Spencer and Gustin wrote. "Damian was present in Pleasant Grove on the date of his mother's death."
The attorneys also wrote in the filing that they don't believe Michele MacNeill was murdered and don't believe Damian MacNeill killed her, but withholding the information from the defense deprived MacNeill of the opportunity to "point the finger at another person," the defense attorneys .
Damian MacNeill committed suicide in January 2010.
In April 2007, Michele MacNeill, 50, was found dead in her bathtub.
According to court documents, MacNeill was having an affair at the time of his wife's death and devised a plan to kill her in order to continue the affair.
MacNeill picked up one of his daughters, Ada MacNeill, from school on April 11, and when they returned home, the girl found her mother in a bathtub that was a quarter full of reddish-brown water, charges state.
MacNeill called 911, but allegedly lied to the dispatcher about performing resuscitation and lied to police about events surrounding her death in an effort to hinder, delay or prevent any investigation, according to the charges.
Spencer and Gustin wrote in their motion that copies of email correspondence found on the thumb drive showed that Alexis Somers, Martin and Michele MacNeill's daughter, had interviewed her younger sister, Ada, about how she found her mother on that day. According to the attorneys, emails and audio recordings show that investigators with the Utah County Attorney's Office had asked Somers to question Ada.
"This is nothing short of astounding," the defense attorneys wrote. "Not only is Ada the second-most important witness in this case against her father, she is a child witness. There are certain protocols that must be followed when interviewing a child witness."
Somers, who attended Monday's hearing, told reporters she has faith in the investigators and prosecutors.
"That's the defense's job to skew the truth," she said. "We know the truth."
MacNeill's attorneys also noted that several other emails found on the thumb drive showed inconsistencies in witness statements from MacNeill's children.
MacNeill has been charged with murder, a first-degree felony, and obstructing justice, a second-degree felony.
In their motion, MacNeill's attorneys asked that if the judge declines to dismiss the charges he should, at the least, disqualify the Utah County Attorney's Office from further involvement in the case.
"Investigators got caught up in the sensational nature of the case and ignored proper protocol in conducting this investigation," the attorneys wrote, adding that the concealed information has made it impossible for MacNeill to receive a fair trial.
After an autopsy in 2007, Michele MacNeill's manner of death was ruled "natural," the result of "chronic hypertension and myocarditis, which are capable of causing acute unexpected arrhythmia and sudden death."
But investigators say MacNeill called the medical examiner multiple times and gave misleading information. In 2010, in a new investigative report, Chief Medical Examiner Todd Grey changed the cause of death to the combined effects of heart disease and drug toxicity. The manner of death was changed to "undetermined."
In recent years, other experts have also reviewed the case. A University of Utah professor of pharmacology and toxicology said he believed Michele MacNeill had taken a potentially lethal dose of medication. A medical examiner in Florida determined the immediate cause of death was drowning and that, contrary to the Utah medical examiner's findings, there was no evidence of acute or acute myocarditis.