"Philosophically, we've changed," said Capt. John Lamb, who oversees the city's traffic operations division. "We are now primarily focused on residential areas and lower-volume areas. We can be more selective in our deployments."

The shift came after Denver council members criticized the deployment on busy streets, saying that it looked like police were trying to make money off of speeding motorists instead of being concerned with neighborhood safety.

"The city isn't in it for the money, and it never intended to be," Lamb said. "We want to improve traffic safety."

Officers still monitor some locations that are not residential, but the number of hours that the vans spend there has been scaled back. Photo radar was used in the eastbound lanes of Interstate 70 at I-225, For example, photo radar was used for six hours and nine minutes in December. The previous December, vans spent nearly 76 hours at that location.

The time saved is being reallocated to school zones, where fines can be doubled, and residential streets where speeding has been a chronic problem, said Sgt. Tom Rowe, who coordinates the department's neighborhood enforcement teams.

North Denver resident Adolfo Dominguez has noticed the difference.

For 14 years, Dominguez has lived in the 4300 block of Steele Street, a residential strip nestled between an industrial area and I-70. He worries about speeding cars because of the children in his neighborhood.

"When we first came here, there wasn't that much traffic, but now it's terrible," he said. "And sometimes it's fast. Cars pass like there are two lanes."

In December 1999, police spent less than three hours in the blocks near Dominguez's house. Last December, the time spent there quadrupled. A continued presence is critical to keeping the problem under control, Dominguez said.

"When the truck is here, it's good," he said. "As soon as the truck takes off, the traffic goes back to normal."