DENVER -- The city of Denver will be allowed to enforce its 15-year ban on pit bulls.

A state law passed last year prohibits cities and counties from singling out certain kinds of dogs, so the city of Denver sued.

A judge in Denver's District Court on Thursday upheld Denver's law, saying that the state Attorney General's Office failed to provide any new scientific evidence in the field of animal behavior or other new information that would make Denver's ordinance unconstitutional.

The same judge had also ruled in December that "home rule" gives Denver the right to ban specific breeds of dogs, despite the state law.

The city said it will start enforcing the pit bull ban on May 9. Pit bull owners have 30 days to remove their dogs from the city, officials said.

Denver banned pit bulls after the Rev. Wilbur Billingsley was attacked by a pit bull in 1989. He was bitten 70 times and both of his legs were broken.

The city sued the state in May 2004 after Gov. Bill Owens signed a state law making owners liable for injuries the first time a dog bites. The bill, which also prohibited cities and counties from outlawing specific breeds, followed the fatal mauling of an Elbert County woman by three pit bulls last year.

The Denver pit bull law prohibits any person from owning, possessing, keeping, exercising control over, maintaining, harboring, or selling a pit bull in the city and county of Denver. The city defines a pit bull as any dog that is an American pit bull terrier, American Staffordshire terrier, Staffordshire bull terrier, or any dog displaying the majority of physical traits of any one or more of these breeds. Copies of these three official breed standards are available at the Denver Municipal Animal Shelter at 678 South Jason St. in Denver. Call (303) 698-0076 for more information.

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