Eyewitnesses describe forceful punch, allegedly thrown by Reece Watherston, that killed Jack Hanley in December 2017

The punch that killed Jack Hanley after a Hindley St fight was thrown “with all possible force” and the thud as he hit the ground was so loud it was heard across a city intersection, a court has heard.

Reece Watherston, centre, has pleaded not guilty to manslaughter. Picture: AAP/ Keryn Stevens.

• Victim ‘trying to get away when killed by powerful punch’
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The punch that killed Jack Hanley was thrown “with all force possible”, causing him to fall to the ground with a “sickening thud” audible across a city intersection, a court has heard.

On Friday, the Supreme Court manslaughter trial of Reece Watherston heard evidence from two people described, by prosecutors, as “independent witnesses” to the groups involved.

Both Andrew Miller and former Mix 102.3 announcer Robert McCasker saw the fatal punch, on the corner of Hindley and Morphett streets, from their cars on December 10, 2017.

Mr Miller, who filmed the incident with his phone from the southbound right-hand turn lane of Morphett St, said Mr Hanley was retreating from Watherston when he was struck.

“He was backing away, jumping away and protecting himself … his head hit flush on the ground … I believe he was knocked out before he hit the ground,” he said.

“The punch looked like it was thrown with all force possible, like (Watherston’s) whole weight was behind it, with force.

“I heard a sickening thud when his head hit the ground.”

Jack Hanley. Picture: Supplied by Mr Hanley’s family.

Watherston, 21, has pleaded not guilty to one count of manslaughter.

Prosecutors allege he struck Mr Hanley after their respective groups of friends had scuffled on the corner, even though Mr Hanley did not take part in the aggression.

The court has heard all the men involved in the events had taken drugs including MDMA, cannabis and “nossies”, or inhaling small canisters of nitrous oxide.

On Friday, the court heard Mr Miller’s former partner had been sitting in the passenger seat of his car when Mr Hanley was punched.

She had described the sound of his head striking the pavement as “a horrible, loud thud” that “sounded like it happened right next to me, even though we were across the road”.

In his evidence, Mr McCasker said he was driving to work when he noticed the scuffle, which had “petered out” before Mr Hanley was punched.

“I recall a man in light-coloured clothing launch a punch at a man in black … it appeared to me his whole body weight was thrown behind the punch,” he said.

“I thought at the time ‘that escalated really quickly’ … it seemed, from what I saw, very aggressive and over the top.

“The man in black fell backwards … the sound I heard was the sound of a rock hitting concrete — it was so loud.”

The trial, before Justice Anne Bampton and in the absence of a jury, continues.

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