Prosecutors in the Martin MacNeill murder trial spent most of the day Thursday trying to show that the former Utah doctor's wife was drugged and drowned when she died. This is the main theory behind the prosecution's case and one they're having to work hard to prove after the medical examiner who performed Michele MacNeill's autopsy determined she died of natural causes on April 11, 2007.
Dr. Todd Grey, the chief medical examiner of the state of Utah, took a second look at Michele MacNeill’s files and said the prosecution's theory is possible, at least in a hypothetical scenario.
“If you were to learn the defendant here had told somebody -- or others -- that he had drugged up Michele MacNeill and convinced her to get into the tub and held her down for a little bit, and it caused her death, would that scenario be consistent with how Michele MacNeill may have died here?” asked prosecutor Chad Grunander.
“Yes, certainly it’s possible,” Grey said.
Martin MacNeill is on trial in Provo, Utah, and has pleaded not guilty to murder and obstruction of justice. His defense attorneys say investigators were so intent on pointing the finger at their client that they overlooked the simple fact that his wife died of natural causes.
The original cause of death certified by Dr. Maureen Frikke said Michele MacNeill died of cardiovascular disease with hypertension (high blood pressure) and myocarditis (inflammation of the heart). Grey said he inherited Michele MacNeill’s case after Frikke died from breast cancer in 2008. The Utah state attorney’s office asked Grey to take a second look at Michele MacNeill's files after evidence of a possible motive for her death (an affair her husband was allegedly having) surfaced.
Grey said he amended Michele MacNeill's cause of death to include the possibility that “drug toxicity” -- or the "adverse effect of drugs on the body" -- may have also played a role. Michele MacNeill was found with several drugs in her system -- including Valium, Percocet, Phenergan and Ambien -- the day she died .
Grey couldn’t say for sure that Michele MacNeill was drowned or that the drugs alone may have caused her death, but he did say it’s a possibility based on the other evidence made available to him from the case.
On cross-examination, defense attorney Randy Spencer read an e-mail Grey initially sent investigators in September 2008, in which he declined to amend Michele MacNeill's cause of death because there was "nothing in the autopsy or toxicology findings that proves her death was from an unnatural cause... the autopsy findings certainly find evidence of natural disease that could explain death."
Spencer went on to suggest that Grey only amended the cause of death almost two years later, in October 2010, because he was being pressured by investigators. Grey, however, insisted that he wasn't pressured and that he changed the cause of death after seeing more evidence from investigators.
Still, despite that additional evidence, Grey couldn't determine that the manner of Michele MacNeill's death was a homicide; he amended it to "undetermined."
Read more: What really killed Michele MacNeill?
"I don’t find anything in the materials so compelling that it overcomes the lack of physical evidence from the autopsy that would prove Michele is the victim of homicide," Grey wrote to investigators in an e-mail dated August 6, 2013.
Prosecutors are expected to continue this same trajectory Friday by calling additional medical experts to the stand to testify about how Michele MacNeill died.
Martin MacNeill faces life in prison if convicted.