DENVER -- Denver Animal Control will not impound a pit bull if the owner claims it’s a service dog.

Animal Control Director Doug Kelley said that’s not a new policy, it’s just now in writing.

“It came as a surprise to us,” said Jennifer Edwards of the Animal Law Center in Wheat Ridge. “And I think it will come as a surprise to many other people.”

The Animal Law Center represents four plaintiffs who have sued the cities of Denver and Aurora in federal court, alleging that their pit bull bans are in violation of federal law.

In an affidavit filed April 5, 2011, Kelley said, “Animal Control officially adopted a written Policy and Procedure permitting disabled individuals to have pit bulls as service dogs.”

Kelley told 7NEWS that if officers identify someone with a pit bull, “That dog is not going to get impounded. We’re just going to find out what function the animal services.”

That may be difficult, because federal law prohibits officers from asking about an individual’s disability.

“I’m not sure what that means,” Edwards said. “It sounds to me nothing short of spying on people as to whether or not the dog is a service dog.”

People who own pit bulls as pets said they’re glad Denver has put its service dog policy in writing.

“It’s a nice step in the right direction,” said Victoria Chenault, who rescued a pit bull from New Orleans 10 years ago. “But it doesn’t go far enough.”

Chenault said her dog, Lily, is a friendly pit bull.

“She’s wonderful around kids and wonderful around other dogs,” Chenault said.

Chenault said she’d like to see Denver drop its ban on pit bulls and focus on vicious dogs no matter what the breed.

Kelley said there’s a reason for the ban.

He said in the 1980s there were several incidents where Denver residents were mauled by pit bulls.

He said the number of pit bulls confiscated in Denver has dropped dramatically and so have the number of bites.

When asked why it took so long to put Denver’s new policy in writing, Kelley said, “The policy hasn’t changed, the city just wanted to make sure that people were aware they could have a pit bull as a service dog.”

He said the city also wanted to make sure that people don’t abuse the service dog rule.