An Auckland grandma who in a rage fatally threw her frail grandson down a hallway has been found guilty of his murder.
Irritable from smoking methamphetamine and furious Jermain Mason Ngawhau had yet another toileting accident, 65-year-old Kathleen Cooper grabbed the toddler on December 13, 2015, prosecutors said.
Then, with a hefty throw, sent him hurtling down the hallway of their Manurewa home, his head smashing into either the floor or wall so hard, it was as if he had been in a high-speed car crash.
The two-year old was rushed to Starship Hospital for emergency surgery, but died five days later.
On Tuesday, a jury at the High Court at Auckland took nine hours to decide Cooper was guilty of his murder.
The grandmother stared at the ceiling after the verdict was read, her eyes welling up.
The key question had not been whether she killed Jermain. Cooper admitted she had and accepted she should be found guilty of manslaughter.
Instead the trial hinged on whether she was guilty of the more serious charge of murder.
The Crown argued she either intended to kill Jermain or knew she was gambling with his life by heaving him into the air.
Prosecutor Aaron Perkins, QC, said the toddler was small for his age and suffered from a genetic disorder that meant he had not yet learnt to walk or use the toilet.
Cooper knew better than anyone how fragile he was, Mr Perkins said.
But Defence lawyer Paul Dacre, QC, dismissed this, arguing Cooper loved all her grandkids.
In 2013, when aged 62, she agreed to take over the care of her troubled daughter's four children, all aged under five.
It was an enormous load for an elderly woman. Why would she do it, if not for love, and how could this love turn into murderous rage just 18 months later, Mr Dacre said.
He said Cooper instead suffered a brain snap because she was under tremendous pressure.
Jermain alone was a handful. Yet Cooper also had to care for his three siblings.
But it was exactly this stress along with Jermain's continual toileting mishaps that pushed Cooper to commit murder, Mr Perkins said.
The toddler was found covered with bruises and Cooper had taken to hitting him, he said.
A witness had seen her swear at the toddler as she dragged him off the toilet, naked and screaming, the day before he died, he said.
The two lawyers also argued about whether Cooper smoked meth in the days before Jermain died.
Medical tests showed the four children had been exposed to the drug and Cooper's nephew also testified he smoked the drug with her.
Incredibly, Cooper also blamed Jermain's death on an older sibling, by, at first, claiming the small child had whacked him with a tablet and then shown no remorse, Mr Perkins said.
She will be sentenced in October.