The High Court in Hamilton has heard that a Ngāruawāhia man died at the hands of a pack of people who targeted him for what he had supposedly said about a gang leader.
Mitchell Paterson, 26, was a methamphetamine addict and was supplying the drug.
His body was found at Mclaren Falls in Bay of Plenty on 13 July, 2018.
Three people are on trial over his death in the High Court in Hamilton.
Gang leader Leon Wilson and Christopher Smith face charges of manslaughter, kidnapping and conspiring to pervert the course of justice.
Chloe Kerridge is accused of kidnapping and trying to defeat justice.
Crown Prosecutor Jacinda Foster said a petty and puerile response to rumour and innuendo drove the targeting of Mr Paterson.
She told the jury that Mr Wilson, who is President of the Nomads gang in Hamilton, ordered others to bring Mr Paterson to him.
Mr Paterson was enticed into a car and held down in the back seat, the Crown said.
Ms Foster said Mr Paterson began struggling in an attempt to escape the vehicle and during that struggle he was restrained in a head-lock or choke-hold, with an arm around his neck.
She said Mr Paterson was taken from a central Hamilton address to Mr Wilson's home in the suburb of Flagstaff.
"Mr Paterson was observed to be blue in the face and unresponsive and he had a small amount of blood visible on his lips."
Ms Foster said attempts were made by various people at the Pohutukawa Drive address to rouse him or wake him but they were unsuccessful.
"The group then discussed throwing cold-water on him or attempting to revive him but eventually they realised he was dead."
The Crown said a plan was then hatched to dispose of the body.
Ms Foster said initially the plan was to burn a vehicle with the body inside but later in the evening the planned changed and Mr Paterson was taken to McLaren Falls.
"Removed Mr Paterson's body from the rear of the Nissan Turano and threw it over the bridge railing into the water below."
The Crown accepts that there was never an intention to kill Mr Paterson.
Ms Foster said Mr Wilson and Mr Smith, by reason of their actions and their involvement that night, were parties to the assault of Mr Paterson.
"As parties to the assault they are parties to manslaughter."
After the Crown finished its opening, Mr Wilson's lawyer Roger Laybourn made a brief opening statement to the jury.
"He never intended to have any violence that could possibly lead to serious injury or death.
"The sad reality is that you can't talk to a person who is brought to you deceased."
The Crown intends to call 40 witnesses in a trial expected to last up to two weeks before Justice Davison and a jury of seven women and five men.
Five other people have already pleaded guilty for their part in Mr Paterson's death.
Mr Paterson was described to the court by the Crown as Waikato-born and raised, energetic, fun, and loyal to his friends.
He was the father of a 6-year-old girl.
The Crown said Mr Paterson got involved in drugs and became trapped by his addiction.