A 23-year-old Sydney woman experiencing a cannabis-induced psychosis was fatally injured when she slipped from a police officer's grasp and plunged 10 metres headfirst onto a road.
Grace Herington had been discharged from hospital hours before she was chased by police and fell off a road ramp in Sydney's lower north shore.
Despite her death occurring as the result of a police operation, State Coroner Teresa O'Sullivan said in inquest findings released on Wednesday "police took appropriate action in the circumstances".
Ms Herington was described as a beautiful, happy woman and a loyal friend. The dux of her school went on to Sydney University in 2015, but felt isolated from her peers.
During her studies she became overcome with stress and in October reported of suffering persistent headaches.
She was prescribed melatonin and given special consideration for poor exam results, and experienced what her family calls a "breakdown" at the end of 2016.
For the first time in 2017 she started experimenting with cannabis and LSD.
After receiving low exam results towards the end of 2018 her brother noticed her behaviour becoming erratic.
After smoking cannabis with a friend on December 15 that year she experienced hallucinations. Three days later she made some bizarre phone calls to her parents where she said she had "stopped 9/11, but I didn't kill [a named person]".
Ms Herington was taken to hospital on December 18 as a voluntary patient, and after assessment "did not display suicidality, wasn't aggressive or overly agitated, and had indicated she would see her psychologist the next day," and was discharged.
After returning to the Hunters Hill unit where she lived with her brother, her unusual behaviour prompted him to call emergency services.
She escaped out her window and paramedics tailed her movements, and police arrived shortly after.
Senior Constable Timothy Shields observed her screaming and running erratically towards the road.
Ms Herington "climbed over a guard rail, lay down along a low cyclone fence and then tipped over the edge" at which point Sen Const Shields took hold of her leg.
But swinging her body he was unable to hold onto her and she fell onto the road.
Her death in hospital from multiple blunt force injuries was described by Ms O'Sullivan as a "tragic end to a young and promising life".