Mr Lester said the Dog Control Act did not allow conditions to be added to a disqualification, such as, in this case, being able to keep the two small dogs.
"Effectively the law does not allow council to grant the applicants' request to retain the two dogs," Mr Lester said.
Ms Vearer and Ms Bremner now have 14 days to appeal this decision in the district court.
Hastings District Mayor Lawrence Yule said the Dog Control Act was quite clear that if a person was banned from owning a dog it applied to all dogs.
"It is an all or nothing provision," he said. "You might look at it and say, well, what are the chances of these smaller dogs causing any harm to anybody else, and on the surface of it, it's probably small.
But the law, as he understood it, did not give the hearings committee any discretion: "You are either allowed to own dogs or you're not."
Speaking in his role as President of Local Government New Zealand, Mr Yule said that there was a lot of work to be done in addressing the dangerous dog issue and unprovoked attacks on other dogs and people.
"That's the work of the government and LGNZ at the moment," he said.
This hearing follows a court case that started in November last year when the owners of the three dogs pleaded guilty in Napier District Court to two charges each of owning a dog that attacked a person causing serious injury.
Ms Vearer was found guilty of owning a dog responsible for causing injury and sentenced to 150 hours of community work. Ms Bremner was convicted of owning a dog that rushes to a person, causing injury, and fined $1500.
All dogs responsible for the attack have been destroyed.