Danai Deneiderhavsein, 19, Finley Goodwin, 23, and Koby Weaver, 22, were arguing loudly on a busy street in Newtown, in Sydney's inner west, on the night of January 22, 2025.
They were described as worked up and aggressive by off-duty police officers Jack Steen and Lachlan Gray, who caught the trio's attention just before 11pm.
Deneiderhavsein shoulder-barged Mr Gray before he and Goodwin fronted up to the police officers, who tried to de-escalate the situation, according to the facts of the case.
During the ensuing brawl, Goodwin threw a hay maker punch while Deneiderhavsein attacked Mr Gray and knocked him to the ground.
The teenager crouched over the officer while continuing to punch him, the court documents say.
The altercation caused traffic to stop when Mr Steen stumbled into the middle of a busy road during the attack.
Footage captured by an onlooker shows him gripping Goodwin's shirt while lying on the road before Weaver stomps on his face with extreme force.
A crack can be heard as the officer's head is slammed back into the road as he is knocked unconscious in mobile phone footage of the incident shown to Sydney's Downing Centre Local Court on Friday.
As Mr Gray moved towards his friend to help, the agreed facts state Goodwin threw a punch at him before fleeing the scene with Weaver.
Lawyers for the trio pointed to their young age, contrition and good behaviour since the offending as reasons they should be sentenced to community corrections orders.
But the prosecutor stressed they had launched a random "unprovoked, repeated and quite brutal attack".
The trio had acted as a pack to continuously attack the innocent men, Judge Greg Grogin, while noting the footage proved the adage that a picture paints a thousand words.
"What can be seen here is a barbaric attack on two men," he said.
The police officers had only retreated and acted in self-defence throughout the confrontation, the judge found.
He took into account Deneiderhavsein's letter of apology but noted he had reportedly minimised the offending afterwards, saying "these things happen in a city".
The teen was fined and sentenced to an 18-month community corrections order and a 12-month jail term in the community after admitting four charges, including reckless grievous bodily harm in company.
Goodwin looked relieved as he received the same sentences for two charges of assault occasioning actual bodily harm in company.
But Weaver was jailed for two years for recklessly inflicting grievous bodily harm in company after Judge Grogin decried how he stomped on Mr Steen's head without provocation.
"It was an act of cowardice, brutal and unnecessary, and the major contributor to the injuries sustained by Mr Steen," he said.
The officer was treated for a bleed on the brain, multiple facial fractures, and swelling after being treated by an off-duty nurse and a member of the public until paramedics arrived.
Mr Gray sustained two black eyes, lacerations and swelling during the attack.
Weaver was reckless and acted like a coward when fleeing the scene afterwards, Judge Grogin said.
But he acknowledged the 22-year-old had demonstrated insight into his offending and had engaged with weekly counselling since being on bail.
"The behaviour of these men on that day was disgraceful," Judge Grogin said.
"They have come to learn the errors of their ways … and they have since taken ownership of their actions."
Weaver hugged his friends and his family before being taken into custody.
His lawyer made a bid for bail after foreshadowing an appeal, but it was dismissed.
