REGINA -- The defense rested its case on Friday, wrapping up two weeks of witness testimony in the second-degree murder trial of Jason McKay, accused of killing his wife Jenny in 2017.

The final witness heard late Thursday afternoon and into Friday morning was an expert called by the defense, Steven Richardson. He is a specialist in psychopharmacology, the study of the effects of chemicals and drugs on brain function.

His testimony followed that of the accused himself, Jason McKay, on Thursday.

Jason told court he had little to no memory of most of the events surrounding his wife’s death, up to and including his time in police custody, citing a blackout state for much of that period.

Following the testimony of the accused, Richardson was called to the stand to speak to the effects of alcohol on the human brain, which commonly includes memory loss and lack of general awareness, depending on the level of consumption.

Richardson said long-term memory can shut down at a certain level of drunkenness, but an unexpected emotional activity can overcome the suppression induced by alcohol.

Under questioning from the defense, he also spoke that an antidepressant Jason was taking at the time, sertraline, can cause amnesia and aggression in some people.

He also testified how taking the drug in combination with drinking liquor can “considerably” reduce the amount of alcohol necessary to induce memory loss effects.

During a break in court, Richardson calculated Jason’s blood alcohol content based on what he remembers drinking after getting home from work on Sept. 5, 2017: four Twisted Teas, and sips of wine. Richardson concluded for the courtroom that his BAC, in combination with sertraline, made it possible to have caused amnesia, adding continued consumption would result in the effects lasting longer.

On Friday, the crown took up its cross examination of Richardson – with “judgement” being the key word, asking Richardson about impairment, blackout, and when Jason was at that level of intoxication.

Richardson argued the thought becomes the action when in a blacked out state – something the crown took disagreement with – leading a lengthy back-and-forth on how “alcohol-induced amnesia” effects judgement, thought, and more.

Although testifying it is difficult to say if Jason was in a blackout state upon his arrest, the crown asked Richardson if Jason appeared sober and lucid in his police interview from the evening of Sept. 6, 2017 shown during his testimony, he agreed. The crown followed up by asking if Jason could still be in a blackout state at that point, Richardson said it was possible.

Richardson did add that by the next morning in custody, the alcohol would be gone and the sertraline would be heavily diluted by the time he spoke to any police if he had not taken it since the morning of Sept. 5.

After some brief follow up questions, the defense rested, leading to an adjournment around noon Friday. Court will be back in session Monday afternoon for closing arguments to the judge.