A UK animal charity wants changes to the law after a "loving and well-behaved" dog was put down for "looking dangerous".
Blue Cross says thousands of dogs are being put down unnecessarily.
"Duncan was in such a sorry state when he came into us," the charity said in a release earlier this week.
"He was skin and bone - you could see his ribs. He also had a really bad infection and sores on his legs. He'd clearly never known a loving home."
Staff said the "gentle giant" was loved by everyone in the Blue Cross team.
"We could have easily helped him find a new loving home."
It's now launched a petition for the UK government to review the Dangerous Dogs Act, which sees many animals "unjustifiably handed an automatic death sentence based solely on looks alone".
"Sadly we see loving and well-behaved dogs like Duncan all too often who have not put a paw out of place and would make someone a fantastic pet, but because of the current law our hands are tied and they are not given the chance to live," said Blue Cross.
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Blue Cross CEO Steve Goody said there's no evidence to suggest that breeds currently deemed dangerous are more likely to show aggression than others.
"Any dog can show aggression if it's incorrectly trained or badly treated. No dog can be assessed on looks alone."
In New Zealand, dogs that are automatically listed as menacing are predominately the type of breed listed in the Dog Control Act, or dogs that are banned from importation to New Zealand.
These breeds are the Brazilian Fila, Dogo Argentino, Japanese Tosa and the American Pit Bull Terrier.
Menacing dogs must be muzzled when in a public place and must be neutered.
Councils will also deem any dog dangerous if they have caused any harm or damage, and they must be kept within a fenced area and muzzled and kept on a leash when in public areas.