Former detectives Roger Rogerson and Glen McNamara are currently behind bars, charged with the 20-year-old's murder.
Police will allege Mr Gao had 3kg of the drug (with a street value of about $3 million) when he met the two men in Padstow, south-west Sydney, in a suspected botched drug deal on May 20.
It is the latest in a surge of serious crimes involving ice, which has officially been declared a "pandemic" in Australia.
An investigation into the drug by The Australian Women's Weekly reveals heartbreaking stories of young lives being destroyed by ice, which has skyrocketed in purity and flooded into regional and rural areas.
Parents, police and paramedics were among those who told what a devastating impact the highly-addictive drug is having on users and those who get hurt when they’re high.
The death of Mr Gao, whose body was found floating off Cronulla by fishermen after he was reported missing, is tragic but not completely against the odds.
The manufacture, distribution and sale of ice in Australia are part of a sophisticated and well-organised crime network, headed by crime kingpins.
As well as record shipments being bought in from Asia, the drug is being produced in clandestine laboratories here in Australia.
The main ingredients can be bought at pharmacies and hardware stores, meaning drug dealers do not depend on supply of overseas crops as with cocaine and heroin.
It is not confirmed where the drugs came from, although detectives are reportedly looking into a suggestion of a link to a large drug seizure involving Chinese students in Auburn on the day Mr Gao died.