Namath, 66, appeared before a hearing officer on Thursday in West Palm Beach to answer to charges that two of his dogs attacked people who came to his home in Tequesta, a quiet community about 90 miles north of Miami.
His 6-year-old yellow Labrador retriever, Leo, was declared "dangerous" during Thursday's hearing. The case against another of Namath's dog, a 6-year-old Weimeraner named Stella, was dropped because a witness didn't show, said Capt. Dave Walesky of Palm Beach County Animal Care and Control.
As a dangerous dog, Leo must now be muzzled and leashed even on Namath's property. It must have a microchip implanted and carry a special "dangerous" dog designation tag. Namath must also now post signs on his property warning of the dog's presence.
An animal control officer will visit Namath's home yearly to be sure he is complying.
If the dog bites someone else, it could be declared "vicious," and euthanized, and Namath could face criminal charges, Walesky said.
"If he moves and doesn't notify us, if he gives the dog away and doesn't notify us, it's a violation of the ordinance and he could be fined," Walesky said.
Namath declined to comment. His New York attorney, James C. Walsh, said Namath might appeal.
Walesky said animal control had received four reports of Namath's dogs attacking people on his property since 2007, "and rumors of many more."
A UPS driver was "accosted by a pack of dogs" on Namath's property in May 2007, Walesky said.
"He's not sure which dog bit him, but he did identify Leo as one of the dogs," he said.
Then in February 2009, a contractor working at the home was reportedly "pinned up against his vehicle and bitten on the wrist," Walesky said. He identified Stella as the culprit, but the man did not appear for the hearing Thursday, so the case against that dog was dropped.
Officials say in May 2008 a home nurse mistakenly went to Namath's home and was bitten by one of his dogs. It was believed to be Leo. Lastly, in August a landscaper was bitten on Namath's property, Walesky said.
He said Namath hasn't acknowledged that his dogs bit anyone.
The legendary quarterback is best known for leading the underdog New York Jets to one of the most storied Super Bowl victories 40 years ago over the heavily favored Baltimore Colts.