NEW YORK (CNNMoney) -Who watches the watchers? It's an age-old question, but police across the country may have a new answer.
The Los Angeles Police Department is currently testing body-mounted cameras that record officers' interactions with citizens. The New York Police Department says it's reviewing the technology.
These police departments, representing the country's two largest cities, are part of a nationwide trend that could fundamentally change the relationship between police officers and the public.
Rialto, with a population of 100,000 and a police force of 115 officers, began experimenting with wearable cameras in 2012. The results, Farrar says, were stunning: a plunge in incidents involving use of force, from 60 in 2011 to 25 the following year. Complaints from citizens dropped from 28 to three, with just four in the past twelve months.
Farrar says he's received inquiries about the program from other departments as far away as Brazil, Japan and the United Kingdom. Dozens of forces in the United States have followed Rialto's lead, with cameras in use in cities including Fort Worth, Texas; Salt Lake City; and Charlotte.
The benefits of the cameras, supporters say, are twofold: They aid in evidence-gathering at the scene of a crime, and they create a record of officers' behavior, providing a check on unnecessary force and abuses of power.
But the cameras also raise major privacy concerns. Without the right legal frameworks in place, the recordings leave open the possibility of abuse.
The ACLU is worried that the bill doesn't include guidelines on when or how citizens can access footage of themselves. The law also doesn't have rules for how long the video can be stored. There's no guidance on when officers are required turn their cameras on and off, putting that power at the discretion of individual cops.
Donna Lieberman, executive director of the ACLU's New York City branch, said the cameras could be particularly important in the Big Apple, where trust between police and citizens in many predominantly black and Latino communities has been eroded by the department's controversial "Stop and Frisk" policy. A judge ordered the NYPD to look into wearable camera technology in a decision last year that ruled the policy unconstitutional.
In Rialto, Farrar said, cops are required to turn on their cameras in any confrontation with a suspect or citizen. The footage is uploaded to computers when they return to the station, and is typically retained for one to three months.
Carlos Miller agrees. The Miami-based journalist runs the website Photography Is Not A Crime, and has been arrested several times while attempting to document the actions of police officers.