George Orwell would hardly be surprised.

Britain, already among the most surveilled societies on the planet, began experimenting with body-worn video cameras on police nearly a decade ago, long before departments in the United States started to adopt the technology.

President Obama said Monday that he intends to ask Congress for funding for to expand such programs, adding to calls from the family of Michael Brown and others that police should be compelled to wear cameras that record their encounters with citizens and suspects.

“There is no question that this is here to stay,” said Michael White, a criminology professor at Arizona State University who has studied the adoption of the technology. “Police chiefs and mid-level managers have been telling officers, hopefully for years now, that whatever they do on the street is being recorded,” whether by surveillance cameras or bystanders holding smartphones. When officers themselves employ the technology, he says, “it has the potential to increase police legitimacy.”

The key word is potential. White, the author of a Justice Department survey of the existing literature on the use of the cameras, found little empirical evidence to support the most of the claims of the proponents and critics of the devices, mainly because the research has been scant.

The earliest studies come from Britain. An assessment of the use of the cameras in the English city of Plymouth in 2006 and 2007 was intended to determine whether the cameras aided officers in gathering evidence and winning convictions — and they did. Time spent on paperwork went down and suspects were more likely to confess to crimes if officers had captured the misdeed on video.

But there was no clear evidence in Plymouth, and in other British and American cities where the use of the cameras has been studied, that their use improved people’s impressions of the police. “Citizen support for use of body-worn cameras remains unclear, as does the impact of the technology on citizens’ trust in the police (e.g., increased transparency and legitimacy),” White wrote in his report.

In an interview, White said that more research is required, and noted that studies of some U.S. cities — including Rialto, Calif. and the Arizona cities of Mesa and Phoenix — show that use of body-worn cameras results in a reduction of citizen complaints about police and in the use of force.

One of the complexities involved in the use of body-worn cameras is the storage, handling and use of the recorded images. Indeed, much of the official guidance prepared by British authorities concerns the technical and legal issues raised by recording innumerable encounters between citizens and law enforcement officials.

As is the case with mugshots and other images captured by public authorities, sooner or later the material can become public — and that opens up a whole new category of video viewing opportunities. London’s Metropolitan Police this May released this video, of a suspect apparently confessing to robbing and stabbing someone, as the department rolled out its use of body-worn cameras. (The acronym GBH stands for grievous bodily harm, the charge for which the person in the video was arrested.)

For a viewing public already used to dash-cam video and police ride-along footage, body-worn camera images may provide more intense and vivid sense of what officers encounter. “So much of what a line officer does in big city and urban policing occurs away from the police vehicle,” White said. “The potential is there to educate the public on the realities of police work.”