He urged judges to use recently beefed up laws to impose prison sentences on people convicted of killing animals, saying such crimes often lead to more violent offences.
"We want to make sure things go in front of the courts and we want to make sure judges set a standard," Mr Dunn said.
In court, Tao entered no plea but told APNZ outside court he planned to plead not guilty on the basis of self-defence over the January 28 incident.
Tao said the pomeranian called Mia, which belonged to a friend of a flatmate, had bitten him on the hand and defecated on his bed.
"I did punch the dog three times but the dog bit me three times," he said.
"I want to say sorry to the dog owner. I did a punch on the dog and I'm very sorry."
Tao said he liked dogs but Mia was not trained and would often go to the toilet on the flat's carpet.
In Apanui's case, he had previously admitted his offending and yesterday APNZ was granted access to a police summary of facts which outlined how he killed his pet pitbull.
The summary says he was walking his dog through Corban Park in Henderson on the evening of November 23.
He picked the dog up by its collar, causing it to "cock her head to one side and scream".
Apanui picked up his dog by it hind legs and threw it to the ground, holding it there as he kicked and punched it.
He then picked the dog up again, raised it above his head and threw it to the ground. Apanui was heard yelling at his dog to get up, but when he realised the dog was dead he walked off.
"In explanation the defendant stated he kicked the dog to discipline it because she was rowdy and nipped him," the summary says.
Apanui will be sentenced in June.
