The south-west Sydney drug dealer who caused the death of a young policeman was selling large quantities of heroin and cocaine to two of the city's most notorious crime families, the Glebe Coroners Court has heard.
But the officers who planned the raid still designated it "low risk".
Constable Bill Crews, 26, died on September 8, 2010, when, following information from a number of informants, police from the Middle Eastern Organised Crime Squad executed a search warrant in the underground car park of a unit complex in Bankstown.
Drug dealer Philip Nguyen jumped out from behind a car and fired several shots, catching the officers by surprise. Constable Crews was killed by a stray bullet from a fellow officer, Senior Constable David Roberts, in the brief gun fight that ensued.
On Wednesday, Senior Constable Roberts told the inquest into Crews' death that he had been told by an informant known as "X" that Nguyen had been selling heroin and cocaine to key figures in the Kalache and Hamze families.
Members of these families have been convicted of offences including drug supply, gun running and attempted murder.
"X" told Senior Constable Roberts that, two nights before the ill-fated bust, Bill Kalache had allegedly purchased half a pound of cocaine from Nguyen, arriving to undertake the deal with "three carloads of associates".
On the day of the bust Senior Constable Roberts again met with X, who told him that Nguyen - whom he had nicknamed "Miyagi" - was about to receive "a further six ounces of cocaine".
"I asked X to attend the unit that afternoon, and again X was there that evening," Constable Roberts said.
Despite this link to the two crime families, Senior Constable Roberts and fellow officer Senior Constable Richard McNally quickly organised a raid which they categorised "low risk".
"These families were involved in serious criminal activities weren't they - drug dealing, gun possession, violent crimes?" counsel assisting the inquiry, Dean Jordan, SC, asked Senior Constable Roberts.
"Yes, that's correct," the officer replied.
"Would that not elevate the operation to high risk?" Mr Jordan continued.
"We had no information that members of either of those families would be present on that evening," the officer responded.
"You can only act on the information you've got ... You can risk-assess yourself out of doing anything. You wouldn't even pull a driver over or attend a domestic," he said.
The inquest continues.
