Senior Mongrel Mob members told a group of men they had to dig up the body of Jason Lines or risk being assaulted.
The men, who are members of the Eastside Gang in Rotorua, had been drinking with the Mongrel Mob members on December 2 last year - the day Lines was buried at an urupa near Rotorua.
The senior gang members instructed eight men to go to the urupa and exhume the body and bring it back to them.
Ryan Lingman, 25, Shannon Apirana, 28, and Sebastien Wineera, 22, appeared in the Rotorua District Court on Monday where they were to stand trial on a joint charge of offering an indignity to Lines' body.
The trio entered guilty pleas to the charge before the trial got under way.
Rhys James Phillips, 25, previously pleaded guilty and was sentenced to 120 hours' community work and Tiger Ross, 18, and Maurice Ututaonga, 21, previously pleaded guilty and were offered diversion.
Two youths had charges against them dropped in the Rotorua Youth Court.
Apirana had also previously pleaded guilty to a charge of failing to stop for police.
Lines, 24, from Rotorua, was an associate of the men and had died when his fishing dinghy capsized crossing the Bowentown Bar, south of Waihi Beach, on November 20.
His body washed ashore seven days later.
A summary of facts released today to the Rotorua Daily Post said there had been tension between members of the Eastside Gang and the Lines family during Lines' tangi and at the wake.
After the funeral, two senior patched members told the men they had been visited by Lines' spirit.
They told the men they had to go to the urupa and exhume the coffin and bring it back to them, the summary of facts said.
They were told they had a choice, but that refusing to do as instructed might result in them being assaulted.
The men loaded a white Isuzu truck with three shovels and straps to tie down the coffin.
Apirana drove the group to the urupa and the men removed the flowers and photographs from the grave and began digging.
All men, apart from Apirana, took turns at digging.
Apirana refused to dig as he was worried about the tikanga (Maori customs) implications and at one point told the others to stop digging, but they didn't listen to him, the summary said.
Meanwhile, police were told by members of the Lines family they suspected his body was being dug up.
About 9.30pm, police arrived at the urupa and found the Isuzu truck parked with its lights off.
By this stage the group had managed to dig about 1m down into the grave but the coffin remained in the ground, the summary said.
When the men saw the police, they panicked and fled in the truck driven by Apirana.
Police tried to stop the truck, but it failed to do so, reaching speeds of 140km/h in a 100km/h zone.
It eventually stopped at the roundabout of Old Taupo and Hemo Gorge Rds after running over police spikes.
The men did not say anything to police but Phillips told police he had been asked to get the body by senior patched members.
He said he felt bad about what they were doing, but did not have much choice in the matter, the summary said.
Judge Tony Snell remanded the men on bail to be sentenced on December 7.
He also ordered the men to attend a restorative justice hearing if the Lines family wished to do that.