TRUE CRIME: Matthew Phelps had a dream. When he woke up, his wife had been killed.

One night in 1943, 16-year-old Jo Ann Kiger was struck with an intense and vivid dream that people were breaking into her home and murdering her family. As she slept, Jo Ann retrieved two revolvers from the family home and fired at the imagined intruders. Instantly, she killed her father and 6-year-old brother, while severely injuring her mother.

In 1987, Kenneth James Parks, a 23-year-old Toronto man, got up from his bed in the early hours of the morning and drove 23 kilometres to the home of his much-loved in-laws. When he arrived, he assaulted his father-in-law, and stabbed his mother-in-law to death. His only memory of the night is standing in a police station, in shock, saying almost robotically, “I think I have killed some people… my hands.”

Kiger and Parks were both acquitted of murder – given they were entirely unconscious when their crimes took place.

Matthew, who woke from his dream to find his wife stabbed to death beside him, has been charged with murder.

In the seven-minute long 911 call, the operator asks Matthew, "What do you mean... what happened?"

"I had a dream,"Matthew responds. "And then I turned on the lights and she's dead on the floor."

"How? How? How?" the operator says.

“There’s blood all over me, and there’s a bloody knife on the bed. I think I did it," and after a lengthy pause Phelps says, "I can't believe I did this. I can't believe I did this."

Earlier that day, 29-year-old Lauren posted a video to her Facebook page, where she enthusiastically touts a product from the candle company she worked for. By all accounts, Laura and Matthew were happy newlyweds, who both loved Star Wars and danced with light sabers at their wedding last year. Matthew does not have a criminal record.

POST CONTINUES BELOW: Why everyone is talking about The Keepers.

Matthew is not the first to claim cough medicine led to acts of extreme violence.

In August 2011, Seattle doctor Louis Chen stabbed his partner 117 times, and killed their two-year-old son in their home. Defense lawyers argued that Chen could not tell right from wrong due to mental illness, and what they termed 'cough-syrup psychosis'.

Despite advocating for the minimum mandatory sentence of 24 years, Chen was sentenced to 49 years in prison in July of last year.

Bayer, the pharmaceutical company that produces Coricidin, the cough medicine cited by Matthew Phelps, issued a statement extending their, "deepest sympathies to this family. Patient safety is our top priority, and we continually monitor adverse events regarding all of our products.

"There is no evidence to suggest that Coricidin is associated with violent behaviour."

But the legitimacy of that statement is in question. Stated side effects of Coricidin include a racing heart, a feeling of being drunk and hallucinations, however, a 2012 study says that a specific ingredient in cough medicines such as Coricidin can cause mania, and leave people, "at risk for violent and self-destructive acts".

There is perhaps added credibility to Matthew Phelps' claim given he was asleep at the time of the killing. 'Homicidal sleepwalking' is a legal argument that states the criminal defendant cannot be culpable given the act was carried out while they were in a sleeplike state, without consciousness or intent.

In Australia, the law states, "a person cannot be guilty of an offence if they were unconscious or asleep at the time that the act was committed. If a person is asleep and therefore not conscious, they cannot have acted voluntarily."

Perhaps it was the cough medicine.

Or maybe it was a case of homicidal sleepwalking.

Or could it be, that Matthew Phelps intended to murder his wife - and the rest is an intentional and calculated diversion.

There is precedent for all possibilities. With his first day in court this week, soon enough, the justice system will decide.