Mickell Bailey has been found guilty of second-degree murder in the deaths of Roxanne Berube, Daniel Miller and Jazmine Lyon.
"The evidence showing that Mr. Bailey shot these three people is overwhelming," Court of Queen's Bench Justice Sterling Sanderman said Friday in delivering his decision.
"These are violent, sudden deaths as the result of a discharge from a shotgun at extremely close range."
Sanderman called the crime scene "devastating."
Judge believed testimony of killer's friends
Hours after the killings on Nov. 28, 2015, Bailey confessed details of the murders to his friends. He repeated his story two days later to his brother and his brother's girlfriend. The judge said he believed their testimony.
"They told the truth from their perspective," Sanderman said. "They gave good, accurate descriptions of what was told to them by Mr. Bailey."
The judge said that conclusion led to an obvious question: "How does he know details about the killings before anyone else? Before the RCMP are on the crime scene. Unless he was the killer."
No evidence of advance planning
But Sanderman told a nearly full Edmonton courtroom he found no evidence of planning or deliberation in the deaths.
"He makes no statements to anyone before that he was planning the killings," the judge said. "No statements after that he planned them."
The prosecutor suggested the 21-year old went to his aunt's home that night to commit robbery and murder. Sanderman found the evidence was equally compelling that they were impulse killings, describing it as a "horrific impulse, beyond comprehension to most human beings."
Because there was no evidence of advance planning, Sanderman found Bailey guilty of three counts of second-degree murder, not first-degree murder as charged.
Bailey showed no reaction to the verdicts from the prisoner's box.
Second-degree murder carries an automatic life sentence with no chance of parole for 10 to 25 years. Because of changes made to the Criminal Code in 2011, Bailey could face consecutive periods of parole ineligibility, up to a maximum of 75 years.
Prosecutor Orest Yereniuk told the court he will make an application for Bailey to undergo psychiatric and psychological assessments. That application will be heard next week, then a sentencing date will be set.
Outside court, a relative of victim Daniel Miller told CBC News he was disappointed the judge did not convict Bailey of first-degree murder.