A man who stabbed a dog with a pitchfork and then hung it from a tree after it attacked his camel has had his convictions for animal cruelty overturned on appeal.

Daniel Brighton, the owner of the Get Wild mobile petting zoo on a semi-rural Sydney property, had been sentenced to three years and four months in prison in June 2019.

Brighton’s camel Alice was attacked by two dogs at 3am in early 2016.

The dogs were “hanging off [Alice’s] neck” and wouldn’t let go, according to a witness, who said that Brighton “had to beat them off with a pole”. Alice’s face, throat and legs were badly injured.

Brighton caught one of the dogs, a bull terrier, which had also attacked him. He tied it to a tree and then, when it had calmed down, stabbed it with a pitchfork at least six times. He left the pitchfork in the dog while he drove to the vet to get pain medication for Alice.

When Brighton came back from the vet he realised the dog was still alive. He hung it from a tree and beat it across the head with a mallet six to eight times. “I will make sure it’s dead,” he told the witness. After he buried the dog, he told the witness not to tell anyone what she had seen.

The RSPCA charged him with two counts of serious cruelty to a dog. He was convicted in the local court and sentenced to at least 26 months in prison.

But the Supreme Court of New South Wales overturned his convictions on Thursday, finding that he had exterminated a pest animal, which is a defence to his charges.

Brighton’s methods were “particularly abhorrent” and ultimately cruel, but they did not constitute a crime, Justice Stephen Rothman ruled.

Although the dog had a collar and a microchip, it had turned wild, and had kangaroo meat in its stomach. The relentless attack on Alice — a “vulnerable, docile animal” — showed it was a pest.

The dog was “a nuisance”, “dangerous” and “menacing”. It had attacked Brighton’s livestock and was a pest animal even though it was subdued when Brighton attacked it.

“The conduct of the deceased dog rendered it, objectively, a pest animal and the conduct of [Brighton] was, objectively, open to only one reasonable possibility, namely, that his intention was to rid himself of (or utterly destroy) this pest.”

Brighton was also clearly trying to kill the dog, the judge ruled.

The witness had said that Brighton was “laughing and joking” while he attacked the dog, and remarked that it “won’t die, it’s alive” when it stood up after the first attack.

That jocularity was “equally consistent with dismay and incredulity at the survival of the dog and the appellant's inability to effect death”, Rothman said.

The judge found that Brighton left the pitchfork in the dog because he thought it was dead. The fact that Brighton didn’t take the dog to the vet with Alice so it could be put down humanely was “reprehensible” but not a crime.

A necropsy performed on the dog found that its injuries probably caused prolonged suffering.

The local court magistrate had used too technical a definition of “pest animal” and “exterminate” when he rejected Brighton’s defence, Rothman said.