Lenny Lavallee has been sentenced to life in prison with no chance of parole for 16 years for the second-degree murder of Nicole Cooney.

Late one evening in April 2016, Cooney and her friend Theresa Butler were out for a walk in the Inglewood neighbourhood in northwest Edmonton. A few days earlier, Butler had broken up with Lavallee after a tumultuous three-month relationship.

Butler asked her friend to take her dog's leash, while she walked ahead. Suddenly she heard Lavallee's voice, then a gunshot.

Cooney, 30, was shot in the back. She died at the scene.

Lavallee was convicted last June of second-degree murder, which carries an automatic life sentence with no chance of parole for 10 to 25 years. The Crown requested 20 years of parole ineligibility and the defence suggested a 10-year period.

On Monday, Court of Queen's Bench Justice Eldon Simpson sentenced an expressionless Lavallee to life in prison with no chance of parole for 16 years.

Simpson referred to the murder as, "a callous disregard for the life of Nicole Cooney, whom he mistook for Ms. Butler," adding, "It defies any logical explanation."

The judge said the victim was completely vulnerable, with no reason to believe her life was at risk that night. Since she was shot in the back, she was unable to take any evasive action.

At the time of the shooting, Lavallee had a court-ordered weapons prohibition and was on probation for a conviction of assault causing bodily harm on a former domestic partner.

Simpson noted he ordinarily would have set parole ineligibility at close to 20 years, but he took Lavallee's background into consideration in lowering it to 16 years.

A Gladue report prepared for the court indicated Lavallee's childhood was filled with domestic violence, physical abuse, drugs and alcohol. Simpson referred to it as "the same, unfortunate, predictable pattern" he sees in all too many offenders.

The judge attributed the shooting to extreme jealousy.

"He remains a danger to the public," said Simpson. "His jealousy remains unaddressed. He has not dealt with the inner turmoil that has brought him to this place in his life."

Lavallee, 36, is the father of seven children. The mother of his children and two of his daughters were in court for the sentencing.

After the judge left the courtroom, the children's mother looked across the room to the victim's family and defiantly yelled, "Are you happy? Go party it up."

Cooney's family declined comment.