A Tasmanian couple will spend at least the next decade behind bars after they were found guilty of shooting dead their former son-in-law.
Cedric Harper Jordan, 71, and Noelene June Jordan, 68, denied murdering Shane Barker on August 2, 2009, in the driveway of his Campbell Town home.
But after a 10-week trial in the Launceston Supreme Court, a jury on Wednesday found the couple guilty of the 39-year-old's murder.
The pair have each been convicted and jailed for 22 years but they will be eligible for parole after 12.
Justice Robert Pearce found there was "no room for doubt" that it was a planned, premeditated and intentional murder.
"Both Mr and Mrs Jordan were motivated by ill feeling towards Mr Barker and a wish to remove him from the lives of their daughter and granddaughter," he said in his sentencing remarks.
The couple believed Mr Barker was sexually abusing their granddaughter, an allegation that Justice Pearce found improbable but added to their motivation for the murder.
Mr Barker was shot four times after returning from dinner with his parents, with three of the bullets striking his back and upper torso.
His body was not found until the following morning when he didn't arrive for work.
The gun used in the murder has never been recovered.
Cedric Jordan, a recreational shooter, was the one to fire the fatal shot although Noelene Jordan was equally responsible for the murder, Justice Pearce said.
"Mrs Jordan must have been aware of the firearm in the car," he said.
"After the crime they told many jointly concocted lies aimed at concealing their role in the crime."
The Jordans have never shown remorse for their crimes but Justice Pearce said he needed to consider their old age and poor health in sentencing.
"There is a chance that, even with allowance for parole, each may spend the whole or a substantial part of their remaining lives separated and in custody," he said.
But Mr Barker's death had a "profound and devastating impact" on his parents, his daughter and the broader community, Justice Pearce said.
The length of the Jordans' jail terms needed to reflect the gravity of the crime.
The couple's 22-year sentences have been backdated to January 2 this year to reflect the 177 days they spent in custody in 2020.
