The New South Wales Supreme Court has heard a man accused of killing a knife-wielding intruder was annoyed but had no intention of killing the man after a chase and struggle.

Key points: Benjamin Batterham is on trial for the murder of Ricky Slater-Dickson, after Mr Slater-Dickson broke into Mr Batterham's home and stole a handbag

Benjamin Batterham is on trial for the murder of Ricky Slater-Dickson, after Mr Slater-Dickson broke into Mr Batterham's home and stole a handbag Mr Batterham's lawyer says his client acted lawfully by chasing and restraining Mr Slater-Dickson, and there was no intention to kill the man

Mr Batterham's lawyer says his client acted lawfully by chasing and restraining Mr Slater-Dickson, and there was no intention to kill the man The judge urged the jury not to be influenced by social media or previous media reports into the case

Benjamin Batterham, 35, is accused of killing Richard Slater over the 2016 Easter long weekend in the Newcastle suburb of Hamilton.

His Supreme Court trial got underway in Newcastle on Monday.

It has not been disputed that Mr Slater entered his alleged murderer's Hamilton home and stole his wife's handbag, which was in his daughter's room.

Neither Mr Batterham's wife nor his daughter were home at the time.

The court heard after the burglary Mr Batterham chased Mr Slater for 330 metres down the street and a struggle ensued.

It was later revealed that Mr Slater was armed with three knives.

In his opening address, crown prosecutor Wayne Creasey SC said at that point Mr Batterham put the victim in a choke hold to the point where he lost consciousness.

He died the next day in hospital, when his life support was switched off.

"It was an act of the accused that provided a significant contribution towards the cause of death of the deceased," Mr Creasey said.

He added that the jury would need to use common sense when carefully considering the charge.

"It is a question to be determined by you, to decide whether you attribute legal responsibility to the accused in the relation to the death of the deceased," he said.

Defence says there was no revenge

Ricky Slater, 34, died in hospital after being chased and restrained after a break-in in Hamilton on Saturday, March 26, 2016. ( Supplied )

Mr Creasey said there was intent due to the sustained nature of the assault on Mr Slater and an element of payback.

"You may very well think that the accused intended to catch that man and he had a legal right to pursue that man," Mr Creasey told the jury.

"Indeed he had a legal right to restrain him, but that does not give him the right to assault him and exact some form of revenge upon the deceased."

Defence barrister Winston Terracini SC said his client acted lawfully, after Mr Slater broke into his home.

"At no time do we say there is sufficient evidence for you to convict this young man of murder, because there was no intention to kill him or inflict serious bodily harm," Mr Terracini said.

"He was not doing anything unlawful or dangerous.

"He is entitled to be annoyed … he is entitled to be very annoyed, but this is where we agree with the crown that he is not entitled to kill a person because of what happened earlier in the night."

Cause of death central to the case

The court was told Mr Slater was obese, with a pre-existing heart condition, and a lethal amount of the drug ice in his system.

When referencing that, Mr Terracini rejected the cause of death as asphyxiation.

"You will hear evidence from a forensic pathologist, who has done more than 10,000 autopsies, that the cause of death is not a result of the deceased being strangled," Mr Terracini said.

"There was a rugby league, rugby union-style tackle and then the deceased man was brought to ground and there is a struggle," Mr Terracini said.

"It is not one-sided and you will hear evidence of the deceased biting him [Benjamin Batterham] and kicking out at him."

He said there were very few injuries on the deceased man, and while there was a struggle it cannot be defined as a violent struggle.

Judge warns jury not to be influenced by press or social media

Mr Batterham's home in Hamilton, Newcastle, where a suspected burglar was attacked after a robbery in the early hours of Saturday, March 26, 2016. ( ABC News: Giselle Wakatama )

The case of Benjamin Batterham has caused debate and division in Australia and around the world.

Supporters allege that everyone has a right to defend their home, or castle, but the crown says Mr Batterham went too far.

The intense coverage is not lost on Supreme Court Judge Desmond Fagan who issued a warning to the jury.

"The burden of proof rests with the crown and your role is to listen to the evidence, you need to keep an open mind about the charge until you have heard everything," Judge Fagan said.

"I mentioned there has been publicity in the past and you are not to search out information about the background on the case on the internet.

"You can be sure that what is relevant to the charge will be what comes out in this courtroom.

"Half-informed commentaries by other people on the internet or via the press won't assist you and you are to disregard all of that.

"It wouldn't be appropriate to ask your friends what they think and you are not to dig around. You have to decide the case on what you hear in this court."

The trial is expected to last between four and six weeks.