'This is war': five on trial over slain bikie boss

After motorbike riders from the Grudge Bringers were beaten up and stripped of their colours, the group retaliated by allegedly killing the president of a rival gang responsible for the attacks.

As he lay in bed watching Netflix in his regional NSW home, 60-year-old Shane De Britt was killed by a single shot in the head from a shotgun in the early hours of January 14, 2020.

The president of Central West chapter of the Bandidos outlaw motorcycle gang had been diagnosed with cancer when he was killed in his Eurimbla house.

"He would have died almost instantly," crown prosecutor David Scully told a NSW Supreme Court jury on Thursday.

Phillip Brian Woods, Brenton James Hayes, Jace William Harding, Brendan James Russell McLachlan and Brian Anthony Farnsworth are on trial for jointly orchestrating the alleged murder.

Each has pleaded not guilty.

The founder of the Grudge Bringers, Woods allegedly planned the shooting with Hayes who owned the Menace Ink tattoo parlour in Wellington where the group would often hang out.

The pair did not attend De Britt's isolated rural property, instead sending Harding, McLachlan and Farnsworth and two other men dressed in black, wearing masks and armed with weapons to the home.

McLachlan has been accused of carrying the 12-gauge Franchi self-loading shotgun and firing the fatal shot.

On Wednesday, the jury heard how De Britt's paranoia a "rat" had called the police on the Bandidos escalated aggression culminating in the alleged murder plot.

Initially De Britt was on good terms with the Grudge Bringers, thinking they were a social club and of no threat to the Bandidos, the jury heard.

The relationship deteriorated after an altercation at Menace Ink with a Bandidos member, suspicions by De Britt that the Grudge Bringers had claimed the Wellington Hotel as their meet-up joint, and thoughts that one of their members had tipped off police about their movements.

A highway meeting and a flurry of chats through the Grudge Bringers' various Facebook groups followed with members becoming more and more irate.

"This is war," Woods texted on September 17, 2019.

"If you're ready to pick up a piece and come cap a few, we be good but are you ready to cross that line?"

In early January, De Britt got wind the Grudge Bringers were gathering firearms, and ordered his bikies to shut down the rival gang by taking their leather jackets and beating up any male member who resisted, the jury heard.

After the alleged murder, the group took an angle grinder to the Franchi shotgun, buried the remaining weapons, and burnt out the Toyota Yaris used to drive to De Britt's house.

In police interviews, the men said they went to De Britt's house to scare and "put the wind up" the bikie head.

"This was very far from just a scare and a touch-up. On the crown case, this was a joint criminal enterprise to kill someone," said Mr Scully.

Barrister John Stratton SC rejected this, saying his client Harding did not visit De Britt's home to kill him.

"His intention was to simply frighten, scare off Mr De Britt so that the threats and the attacks on the Grudge Bringers would end," he said.

Representing McLachlan, barrister Sam Pararajasingham said his client was not the one to pull the trigger despite admitting he was there on the night.

"He denies the charge of murder," the jury was told.

The trial continues Friday.