Serious dog attacks in Christchurch have prompted the city's council to ask for menacing dogs to be muzzled at all times, even inside the owner's house.

Photo: AFP

The council said it had recently sought legal advice about the interpretation of the Dog Control Act for menacing dogs, and was advised that muzzling was required even when the dog was inside a house or on the owner's property.

Council chief executive Karleen Edwards said in light of that advice the council sent letters to 159 dog owners outlining their obligations.

The letter asks for menacing dogs to be muzzled at all times, including on the owner's property and inside the house.

It said the only exception was when the dog was in a cage or motor vehicle.

Ms Edwards said following the legal advice they wanted to proactively communicate what that meant to owners of menacing dogs.

"We acknowledge that this letter has come as a surprise, because of the interpretation that is now being applied. We are urgently seeking further legal advice on this interpretation to ensure we are doing the right thing."

She said once the council has this clarification, it would get in touch with all owners of dangerous and menacing dogs, to help them understand what was required of them.

"The last thing we want is for someone, or another animal, to be hurt in a dog attack," said Ms Edwards. "So while we wait for this clarification, we simply ask all dog owners to take reasonable steps to keep their dogs under control and meet requirements of the menacing and dangerous dog classification."

She said in the last year the council has had to investigate 234 complaints about dogs attacking a person, stock, poultry or domestic animals.

Dogs are classified as menacing if they have attacked or shown aggressive behaviour which the council says indicates they pose a threat to people or animals, or if they are predominantly or wholly certain breeds. The breeds classified as menacing are Brazilian Fila, American Pit Bull, Dogo Argentino, Perro de Presa Canario and the Japanese Tosa.

However, the SPCA said the council would be breaching the Animal Welfare Code if it enforced the requirement.

Chief executive Andrea Midgen said the SPCA had contacted the council to express its unhappiness with the decision.

"The chances of the dogs involved being compromised is very high...It hinders their ability to breathe really well, to eat, drink. And if it is sick it would compromise that. It is just not a good look."

Abbey van der Plas, who set up Christchurch Bull Dog Rescue, said the council's demand was cruel and stupid.

"A dog's natural behaviour is to clean its self, is to drink water when it needs to. A dog's nose and muzzle are its arms and legs, and if I tied your arms and legs behind your back and told you to live a functioning life, you would have some questions for me."

Ms van der Plas said the council also had no ability to enter people's homes to check on muzzling.

"We're more than happy to fight this in court. I will not be placing a muzzle on my dog in my own home and I will be very vocal about that and I will be encouraging other dog owners to flout this law - because it's stupid."

Some Christchurch residents were divided on whether they supported on the move.

One dog walker said he did not think the restriction should apply to specific breeds, but could understand why a dog should be muzzled at all times if it has previously bitten someone.

Photo: RNZ / Rachel Graham

Another dog walker, Hayden O'Brien, who was walking with Kingston and 13 week old Tricksy, said sometimes people were fearful of his dog Kingston because of his size, but he'd seen far more aggressive little dogs.

Mr O'Brien said he didn't believe the rule would reduce the number of dog attacks, as often it was the owner to blame for problem dogs, and those people did not make their dog wear a muzzle.