The London Metropolitan Police Service (MPS) is set to launch a one-year pilot project that equips cops with body-worn video cameras to be used during their interactions with the public. The pilot will include a total of 500 cameras distributed across ten city boroughs.

The 31,000-officer-strong MPS is not the first police department to deploy systems designed to track its officers. Across the pond, for example, the Boston and Los Angeles Police Departments have installed self-monitoring systems on police cruisers, while dozens of US police departments, including those in Fort Worth, Las Vegas, and New Orleans, have deployed wearable police cameras.

The MPS chose to purchase 500 Axon body-worn cameras alongside a backend management system from Taser International, a manufacturer of law enforcement products and electrical weapons. The body-worn cameras in question are small, battery-operated devices that can attach to sunglasses, a shirt collar, a cap, or a head mount and can record wide-angle, full-color views of the officer’s visual field, according to a press release. A red "flash" appears on such devices to indicate when the camera is activated.

Taser has indicated that London's test is the largest such urban pilot anywhere in the world. Two response teams on each borough will be suited with such cameras when answering emergency 999 calls during the pilot. The findings of the pilot will be used to determine future implementation of such technologies.

"Our Axon body-worn cameras are a game changer for law enforcement agencies worldwide and are helping police officers reduce crime and build safer communities,” Jeff Kukowski, Taser International’s chief operating officer, told Ars. “When you look at community safety today, there are any number of scenarios where there is controversy. Video helps pool together what happens."

Taser’s press statement further cites a study examining the cameras' effects on a small police force in Rialto, California, that the company alleges “showed an 88 percent reduction in citizen complaints and a 60 percent reduction in uses of force after implementation of Taser's Axonflex BWV cameras.”

MPS Commissioner Sir Bernard Hogan-Howe said, "Video captures events in a way that can't be represented on paper in the same detail, and it has been shown the mere presence of this type of video can often defuse potentially violent situations without the need for force to be used."

Don’t shoot!

While Kukowski and Hogan-Howe tout the potential for such technologies to improve the quality of policing, reduce instances where force is used, provide accountability, and serve as valuable evidence in criminal proceedings, some cops have been less than enthused about recording their interactions with civilians.

For example, a New York Police Department officer on Tuesday appears to have forcibly prevented a bicyclist who ran a red light from recording their subsequent interaction.

The cop’s alleged justification for doing so, according to the cyclist, was that “recording a police officer was illegal because people are using iPhones as guns and shooting cops through the camera lens.” The bicyclist spent 13 hours in lockup and was charged with resisting arrest, obstruction, and criminal mischief for what he believed was an exercise of his constitutional right to record a public interaction with a cop.

The NYPD Patrol Guide Section 212-49 states, “Members of the service will not interfere with the videotaping or the photographing of incidents in public places. Intentional interference such as blocking or obstructing cameras or harassing the photographer constitutes censorship.”

The officer that wears it

Cops aren't the only ones who have questioned these surveillance systems.

Privacy advocates like the American Civil Liberties Union (ACLU) have argued that the efficacy of police body-mounted cameras as a crime reduction and accountability tool hinges on enforcement of good policies and procedures—including something as basic as preventing officers from being able to deactivate the cameras at their own discretion.

Indeed, Taser's Kukowski said that his firm's cameras "protect the chain of custody the entire way along," noting that there is "complete auditability on everything that's ever happened during the entire life-cycle of the system."

For now, the ACLU is withholding judgment.

“If the departments have good policies regarding the footage that bans surreptitious recording, includes an exclusionary remedy when the camera’s selectively turned off by officers at the wrong time, et cetera, they can be great,” Kade Crockford, of the ACLU Massachusetts, told Ars. "If used correctly, cameras can be beneficial to reduce police brutality and can aid accurate record-keeping. But we’re waiting to see how they’re implemented.”