Howard County Police Pfc. Robert Radnoff holds his patrol dog, Tomy, in plain sight of trainer Tom Harding and issues a stern command in German: "Revere."
On cue, Tomy sprints across the Police Department's parking lot and then barks aggressively at Harding, who is standing still. But as soon as Harding steps to the left to run, Tomy clamps down on his right forearm, which is wrapped in protective gear.
Howard County police recently finished training their four patrol dogs in this increasingly popular - and controversial - technique, called "bark and hold." Over several years, the dogs are taught to corner and snap at suspects, rather than attack them, unless they move.
It is an alternative to the "bite and hold" method, in which dogs are more often kept on leashes or within a handler's sight and given the order to bite when the suspect is spotted, said Bob Eden, an expert on police-dog training and an advocate for this technique.
"Bite" dogs increase a department's liability, according to bark-and-hold proponents. The International Association of Chiefs of Police recommends the barking method, and neighboring Prince George's County is under a court order to train its dogs this way after a federal investigation into the handling of its dogs.
Howard County's decision to train its dogs in this method did not stem from any incident, said Sherry Llewellyn, spokeswoman for the Police Department.
"The decision to go to bark-and-hold training for our K-9 unit was one that was made in order to be pro- active ... and we believe it was a wise one," she said.
Said Harding, who began teaching four of Howard County's German shepherds the bark-and-hold technique in 2002: "We don't want anyone to get bit - even the bad guy - if we can avoid it."
Harding, who has spent 18 years with Howard's police-dog unit, works with each of the county's four patrol dogs and their handlers five hours a week. He uses a bright green rubber toy as a reward for good behavior.
"Dogs are creatures of conditioning," he said. "They know that if they do things a specific way, they're going to get a reward."
The bark-and-hold method originates from the German dog sport, called Shutzhund, or protection dog. The dogs are judged on tracking, obedience and attack.
In one exercise, the dog is sent to search for a hidden person. When the person is found, the dog is trained to bark unless the subject moves.
Like Harding, the hidden person in such exercises knows how and when to move, even skilled enough to know what kind of eye contact will make the dog jump. The subject wears protective gear and is not afraid of the dog.
Eden said real suspects don't act so rationally - they panic or try to talk to the dog. The resulting interaction between dog and suspect can be unpredictable.
"In a demonstration, the trainer makes a step and the dog bites," Eden said. "But in the real world, that step could just be a guy stumbling around drunk. Unless a handler gives a verbal command, how is that dog to know whether he's a bad guy?"
In those situations, he said, "bite" dogs are more secure "because only the handler can give the order to attack."
Eden praised the amount of time Harding spends training the dogs, but he says that most police departments that use the bark-and-hold method don't have the time or money to invest in such in-depth training - a fact that can lead to failures.
"It's a high-maintenance program. They just don't spend enough time training," he said.