Niko is not a bad dog, according to his family.

McKees Rocks police had never had any trouble with the dog, either. The 2-year-old male pit bull terrier is neutered, has a valid license, is microchipped and up to date on inoculations.

On April 25, Niko did a very bad thing.

He bit a man, inflicting a permanent, disfiguring injury. Niko's actions will cost his family hundreds, if not thousands, of dollars because on June 3, District Judge Mary Ann Cercone invoked state law and declared Niko to be a dangerous dog.

Here's what happened, according to testimony from that hearing:

Jeff Allen, 54, of Stowe, was walking through Herbst Alley looking at a building he was considering buying and converting into a chocolate factory. A barking, growling dog jumped the fence behind a house at 110 Church Ave.

"I screamed for somebody to get the dog," Mr. Allen testified. "He charges at me. ... He leaps at my lower legs. ... I fall down. I am kicking and screaming trying to keep the dog away from me."

Mr. Allen pulled a pen knife from his pocket and "poked" at the dog. "I got him a couple times near the snout."

He heard a girl screaming, "Don't hurt the dog!"

"I am screaming for somebody to get the dog. ... I am starting to panic. ... The dog lunged at my face. I put my left hand up to push him away from my face. At that point I am bitten."

David Killian, 44, ran from the house and grabbed the dog by the collar.

That's when Mr. Allen realized the dog had bitten through skin and bone, severing the tip of the middle finger of his left hand.

Mr. Killian helped look for the finger tip and got ice for the wound while Ellena Adkins, who co-owns the dog with Mr. Killian, called 911.

Medical bills total $1,700. A plastic surgeon said the fingertip could not be reattached.

Defense attorney William Stockey called family members and two neighbors to the stand. They said Niko has never bitten anyone, has never jumped the fence, and is gentle with small children and other dogs.

Mr. Stockey suggested Niko was protecting his family and property from a stranger. "One occasion" does not make Niko what Pennsylvania law describes as a "dangerous dog," he said.

McKees Rocks Police Chief Robert Cifrulak testified that the injury inflicted by Niko "would classify it as a dangerous dog. I don't believe there was any testimony to indicate Mr. Allen provoked the dog. It's a public right of way, and he had every right to be walking there."

Judge Cercone ruled "this dog did attack without provocation, in my judgment." She found Mr. Killian guilty on one count of harboring a dangerous dog and fined him $100. She also said Niko is a dangerous dog, and this is where it gets expensive for Mr. Killian and Ms. Adkins.

They will have to pay $500 per year to register Niko with the state. They must build an escape-proof enclosure. They'll have to get a $50,000 surety bond with their homeowner's or renter's insurance. Niko must be muzzled when outdoors.

Mr. Killian is unemployed. Ms. Adkins said she and her five children are on welfare. Mr. Stockey said Mr. Killian is appealing the verdict.

McKees Rocks police, animal control officers and Judge Cercone used existing state law to protect the public. The law does not mandate euthanasia for a first-time offender. Niko gets a second chance, although many dog owners are unwilling or unable to afford what the law requires.

Radio talk show hosts have been screaming in recent weeks that all pit bulls should be banned or even killed. Current state law prohibits targeting specific breeds. People who rescue and own pit bulls say authorities should "judge the deed, not the breed." And that's what has happened with Niko.

Dog owners must protect the dogs they love. Dogs need care, training and fences that they can't jump. Dogs must always be closely supervised, especially around young children, who are the most frequent dog bite victims.

Most pit bulls will never hurt anyone. Breed-specific legislation unjustly targets dogs like the big white pit bull that is walked through my neighborhood. The owner proudly tells everyone that his dog just earned a "canine good citizen" degree and is working toward therapy dog certification.