As the American public debates the ethics of wearable cameras, such as the one incorporated in Google Glass, police in several cities are already testing their usefulness.
The Los Angeles Police Department recently equipped a number of its police officers with body mounted cameras that must be turned on whenever officers interact with citizens.
Cities like Forth Worth, Texas, and Charlotte, North Carolina, have been testing them for more than a year.
A year after the cameras were introduced in Rialto, California, the town's police reported a record drop of more than 50 percent in incidents involving force.
Observers, however, say the wider usage of wearable cameras should be accompanied by laws.
Supporters of the measure say the video footage helps gather the evidence and keeps officers in check against possible abuse of power, but the American Civil Liberties Union is calling for stricter regulations.
Rialto police say they have received inquiries from police in other countries, including Brazil, Japan and the United Kingdom.