A man who helped bury murdered Sydney man Jacob Munro (pic) was afraid he "might be next".

Killers dug bush grave before NSW murder

Nine days before Jacob Munro was killed, his killers set out to a woodlands and tunneled his grave. 

To check it was the right size, one of them hopped into give it a shot. 

By then on July 22, 2014, Stanley Robert Forward and Donald John Cameron cut and tasered the 24-year-old to death. 

He was represented truant and following five months was found in the grave at Bulahdelah State Forest, north of Newcastle. 

Mr Munro's mother, Deborah Hall, did not know her kid was dead until specialists went to her approach to exhort her his body was in a recuperating focus burial service home, and also had been there for six weeks. 

Forward, 23, and Cameron, 64, have surrendered in the NSW Supreme Court to executing Mr Munro and to purposefully taking an interest in the advancement of 664 cannabis plants. 

A third man who can't be named is in like manner required in regards to the manslaughter, and a fourth, David Ian Wilkinson, 70, has admitted to cannabis advancement and what's more getting, harboring, keeping up and sending, knowing he had murdered Mr Munro. 

In the midst of a sentencing hearing on Friday, Forward's mother gave evidence that her kid had been constrained into the wrongdoing. 

"'They made me. They said they'd butcher me'," she said, refering to her kid who was crying strongly in the dock. 

Regardless, the police had no such announcement on record, the court tuned in. 

"There's no affirmation from (Forward's) record of meeting that he was direct crippled," crown prosecutor Richard Herps said. 

Honestly, Forward supplied the sharp edge and volunteered to be the one to wound Mr Munro, Mr Herps said. 

Value Desmond Fagan said unmistakably Forward, Cameron and the mysterious man all had some part in orchestrating Mr Munro's crime. 

"Exercises talk louder than words, especially words after the event," the judge said. 

The dead man's mother told the court her "existence stopped" the day she found her youngster was no more. 

"I didn't understand that such a dull spot existed in my soul," she said in a composed by hand loss influence enunciation. 

"The day I got word that the last catch had been made I expected to drive on a quiet road. 

"I was going to drive straight into a tree as I thought: 'It is over now'. The courts can oversee it since I can't any more." 

The listening to continues on Wednesday before Justice Fagan