A Tasmanian mother who killed a motorcyclist while driving drunk on the wrong side of a highway has had an appeal against the length of her sentence dismissed.
Kristel Cee-Ann Cowen was in June sentenced to up to six years behind bars for the manslaughter of Dion Hardy, 48, on an October night two years ago.
Mr Hardy, riding a Harley Davidson after leaving a BBQ, was thrown from his bike when Cowen crashed into him on the Brooker Highway.
He died almost instantly.
Cowen was four times over the legal blood alcohol limit at the time and travelling 62km/h in a 40km/h zone.
She also had prescription drugs in her system.
Her lawyer Todd Kovacic argued in Hobart Supreme Court on Friday her sentence was manifestly excessive.
"It was accepted that she was under a lot of stress. People make bad decisions when they are under stress," he said, noting a traumatic experience in the fortnight before the crash.
Mr Kovacic accepted Cowen, who had 34 prior traffic convictions, knew she should not have gotten behind the wheel of the car.
The full bench of the Supreme Court deliberated for about 10 minutes before dismissing the appeal.
Justice Alan Blow said Cowen's non-parole period of four years' jail was lengthy but not manifestly excessive.
© AAP 2018