THE BURNED OVER DISTRICT

But if the experience of one California town holds true, putting a camera on each cop improves the quality of police work.

“You’re being videotaped.”

It is a warning that is transforming many encounters between residents and police in this sunbaked Southern California city: “You’re being videotaped.”

Rialto has become the poster city for this high-tech measure intended to police the police since a federal judge last week applauded its officer camera program in the ruling that declared New York’s stop-and-frisk program unconstitutional. Rialto is one of the few places where the impact of the cameras has been studied systematically.

In the first year after the cameras were introduced here in February 2012, the number of complaints filed against officers fell by 88 percent compared with the previous 12 months. Use of force by officers fell by almost 60 percent over the same period.

And while Mayor Michael R. Bloomberg railed against the federal court, which ordered New York to arm some of its own police officers with cameras, the Rialto Police Department believes it stands as an example of how effective the cameras can be. Starting Sept. 1, all 66 uniformed officers here will be wearing a camera during every shift.

William A. Farrar, the Rialto police chief, believes the cameras may offer more benefits than merely reduced complaints against his force: the department is now trying to determine whether having video evidence in court has also led to more convictions.

But even without additional data, Chief Farrar has invested in cameras for the whole force.

“When you put a camera on a police officer, they tend to behave a little better, follow the rules a little better,” Chief Farrar said. “And if a citizen knows the officer is wearing a camera, chances are the citizen will behave a little better.”

Everybody behaves better when you remove the bullshit factor.