A Perth mother with a long history of drug use, who admitted unlawfully killing her five-month-old son but claimed she had no memory of it, has been jailed for eight years.
Melissa Louise Bulloch, 27, pleaded guilty to the manslaughter of her son Lochlan, who was found dead at his Hamilton Hill home in January 2014.
Lochlan suffered severe brain injures, bruising to his head and neck, and also had meth in his system although that did not contribute to his death.
Bulloch appeared to show no emotion as she was sentenced in the West Australian Supreme Court on Monday.
Justice John Chaney said Bulloch's conduct involved a significant degree of violence and trauma on an extremely vulnerable child who depended on her for his safety.
He said Bulloch's drug use was out of control and affected her parenting, causing her to act impulsively and unpredictably.
Justice Chaney accepted the baby's death was "a source of considerable distress" for Bulloch and she had developed some degree of remorse.
Prosecutor Carmel Barbagallo previously told the court Bulloch's abuse of the infant in the months leading up to his death included having cannabis smoke blown into his face, being left in a car and being shaken and sworn at.
The court heard the Department for Child Protection was also involved with the family and police listened to Bulloch's phone calls and conversations after the baby's death.
On one occasion, Bulloch said: "I'm sorry Lochlan ... for killing you, my sweetheart. That freaked me out."
In a letter read to the court, Bulloch said she was beyond sorry for what happened and wished she could take it back.
"I live every day knowing that I won't be a mother to him and watch him grow up," she said.
Bulloch had her sentence backdated to December 2014 when she was taken into custody and will be eligible for parole in December 2020.
