A man who smoked 50 or more marijuana hookahs a day first claimed to be God, then became a police officer, and then took the drugs from another man and tried to stab him.

Billy Jo James Brown, who was homeless at the time, admitted stabbing Duck but claimed he did so in self-defense while being pursued.

The 37-year-old man pleaded guilty to charges of recklessly causing grievous bodily harm, as well as impersonating a police officer, stalking and intimidating, and unexcused possession of a knife in a public place.

He was sentenced today by District Court Judge Penelope Wass SC to three years behind bars; The 22-month non-parole period dates back to the time of his arrest, making him eligible for immediate release.

The stabbing occurred during an argument between the men; Brown took out the knife and swung it at Duck twice, and Duck shouted: “Did you just stab me?”

Judge Wass noted Brown started using drugs when he was only eight or nine years old and had a history of serious mental health problems, including drug-induced delusions and psychosis.

“He eventually increased his marijuana use and reached the extraordinary level of 50 or more hookahs a day,” he said.

At around 9.30pm on the day of the incident, Duck was staying with a large group of friends at Tiona Holiday Park, south of Forster, and decided to go night fishing.

The group encountered Brown sitting by the water. Brown had been given temporary accommodation in the park at the time, but was due to be kicked out the following Monday, leaving him homeless.

When Duck, who had been drinking, began smoking marijuana, Brown approached the group and told him to hand over the marijuana, saying “I am God” when asked who he was.

Brown then said he was a police officer and told Duck, who claimed the cannabis had been legally prescribed: “Fuck give it to me – you need to prove it, show me the prescriptions”.

Brown followed the group as they continued socializing and returned to the campsite, causing Duck and the others to confront him, leading to an argument.

The charge of impersonating a police officer was dismissed after Judge Wass found there was no evidence anyone seriously believed his claim was true.

“It was delivered by a man who had just declared himself God, who was not wearing a uniform and had no police identification or equipment,” he said.

While the charge of carrying a knife in public was also rejected, a conviction was given for stalking and intimidation, and no other punishment was given.