Albuquerque, Fort Worth and Oakland have all begun arming officers with tiny video cameras. And demand for the devices has exploded in recent years, according to Taser International, one of the companies marketing body cameras to law enforcement agencies.

Experts increasingly say that body cameras are likely to become an industry standard over the coming years, just as cameras in patrol cars, which once prompted similar objections about privacy, have become commonplace in recent decades.

William J. Bratton, who has led the police departments in New York and Los Angeles, said that if he were still a police chief, he would want cameras on his officers.

“So much of what goes on in the field is ‘he-said-she-said,’ and the camera offers an objective perspective,” Mr. Bratton said. “Officers not familiar with the technology may see it as something harmful. But the irony is, officers actually tend to benefit. Very often, the officer’s version of events is the accurate version.”

Still, the technology has proved divisive. Police officers and citizens alike have bristled at what they see as the latest incursion of Big Brother. In New York City, the Patrolmen’s Benevolent Association called the equipment “an encumbrance.” Privacy advocates worry that video of police officers searching a suspect’s home could end up on the evening news.

“The body camera issue opens up certainly more questions than it answers,” Raymond W. Kelly, the commissioner of the New York Police Department, said Sunday on “Face the Nation.” “The only place that this has been implemented are cities that are much, much smaller.”