After refusing his wife's request for a divorce for years, Richard Dudley Kelsey decided to get rid of her.
He recorded Gail Kelsey venting for hours, grabbed a rifle from his bedroom safe, returned to the verandah and shot the 67-year-old at close range in the abdomen.
The now 76-year-old with "murderous intentions" loaded a second bullet but Mrs Kelsey fell off the chair and slumped to the ground in what would have been an agonising death, a court has been told.
"It would have been made all the more painful as she would have spent her final moments trying to comprehend what you, her husband of 28 years, had done to her," Justice Lincoln Crowley said on Friday as he sentenced Kelsey to life in prison.
Without any concern for his wife after the shooting, Kelsey went inside and accessed a bank website to transfer money without being charged interest before calling emergency services.
Family and supporters sitting in two separate groups cried as Kelsey was found guilty by a Brisbane Supreme Court jury that listened to evidence across four days and deliberated for less than five hours.
Kelsey had offered to plead guilty to manslaughter at the start of the trial over his wife's death at their Chambers Flat home, south of Brisbane, in November 2019 but that plea was not accepted by prosecutors.
The court was told the couple's relationship had deteriorated, with Kelsey saying they should have divorced 15 years earlier.
"I had a gutful, just wanted to get rid of her, the divorce and everything," Kelsey told police.
"She goes on and f***ing on and on and on, and I said f*** it - boom - just shot her."
Family had to process fresh pain hearing about the callous disregard Kelsey had for his wife as she lay dying and the realisation the decision to kill her mother comprised no more than a "f*** it thought process", Mrs Kelsey's daughter Jacinta Pannowitz said.
"My mother's truth is this: for nine years she begged for a divorce and for nine years she was refused - not because he loved her but because he loved his house and his bank account," Ms Pannowitz said.
"She's not the tyrant in this - she is a victim who tried until her very last breath to be heard."
Kelsey's reaction to his wife's words was beyond all comprehension, Justice Crowley said.
"You acted deliberately, selfishly and out of anger," he told Kelsey.
"You resented your wife, you wanted her gone but you never had the guts to give her the divorce she wanted."
Kelsey would likely die in jail but a sentence of life imprisonment was the only one that could be imposed for murder, Justice Kelsey said.
Kelsey has been in custody since the day of his wife's death and will be eligible for parole after 20 years behind bars.
Australian Associated Press
