A study has found that body-worn video technology is most effective in preventing escalation during police-public interactions.
The study also added the knowledge that events are being recorded creates 'self-awareness' and averts abusive behaviour towards police or unnecessary use of force by the police.
This turns body-worn video into a "preventative treatment", causing individuals to modify their behaviour in response to an awareness of "third-party" surveillance by cameras acting as a proxy for legal courts.
"The 'preventative treatment' of body-worn-video is the combination of the camera plus both the warning and cognition of the fact that the encounter is being filmed," said Barak Ariel from from University of Cambridge's Institute of Criminology (IoC).
"In the tragic case of Eric Garner, police were not aware of the camera and did not have to tell the suspect that he, and therefore they, were being filmed," Ariel said.
On July 17, 2014, Garner died in Staten Island, New York, after a police officer wrestled him to the ground in a chokehold.
Michael Brown, an unarmed black teenager, was reportedly shot and killed Aug 9 by Darren Wilson, a white police officer, in Ferguson, Missouri.
On Dec 23, a white police officer reportedly shot a black teenager to death at a gas station, less than five miles away from Ferguson.
"With institutionalised body-worn-camera use, an officer is obliged to issue a warning from the start that an encounter is being filmed, impacting the psyche of all involved by conveying a straightforward, pragmatic message: we are all being watched, videotaped and expected to follow the rules," Ariel said.
The team has now published the first full scientific study of the landmark crime experiment they conducted on policing with body-worn-cameras in Rialto, California in 2012.
During the 12-month Rialto experiment, use-of-force by officers wearing cameras fell by 59 percent and reports against officers dropped by 87 percent against the previous year's figures.
The results have been cited by the police departments around the world as justification for rolling out this technology.
US president Barack Obama recently promised to spend $75 million of federal funds on body-worn-video to try and stem the haemorrhaging legitimacy of US police forces among communities.
Ariel conducted the crime experiment with Cambridge colleague Alex Sutherland and Rialto police chief Tony Farrar.
