In my wife’s craft room, if the TV is turned on, something British is playing — and it’s either “Downton Abbey,” reruns of “Upstairs/Downstairs,” or a mystery.

Soap operas, even ones with Limey accents, aren’t my cup of Earl Grey, but I like the detective stories.

Fans of the CSI series of American crime-lab procedurals (the ones that make you wonder why police forces hire detectives, since the crime-lab scientists not only investigate crimes but perform the arrests and conduct the interrogations) know what it takes to identify the perpetrator.

Oh, fingerprints have a role, but for really nailing down a perp, the question on which everything hangs is, “Do we have the DNA?”

In fact, real-life prosecutors have been heard to complain that TV-saturated jurors can doubt even airtight evidence if there isn’t any DNA to “really” prove the case.

But in the modern-day British mysteries, it isn’t DNA for which the cops are waiting. Instead, they ask, “Do we have video?”

And usually the answer is, “Yes.”

That’s because, as the United Kingdom’s Daily Mail newspaper headlined a couple of years ago, “Shocking study reveals UK has one closed-circuit television (CCTV) camera for every 32 people” — and it’s undoubtedly gone up since then.

Despite their ubiquity, cameras remain controversial there, but Americans should understand that many U.S. law enforcers view our relative lack of comprehensive street surveillance as a bad thing, and want to start catching up with the Brits.

And not just with CCTV, but with a variety of drone aircraft, far smaller and less obtrusive than the big military models.

The Daily Mail said a 2011 survey found 1.85 million CCTV cameras, both public and private, watching citizens’ actions day and night.

Many of them have been equipped with systems to identify cars’ license plates automatically, and if attached to “facial recognition” computer programs, can even identify people walking down the street.

Studies show they are most effective in preventing crimes in parking lots (with a 51 percent reduction), less so in public transportation settings (23 percent), and have had almost no effect in reducing common street crimes (7 percent).

What’s the point? Because the identification of the Boston bombers with street cameras (in this case, private ones owned by stores) has raised both interest and support to use more CCTV cameras to prevent and solve crimes here in the States.

In “Caught on camera: Boston manhunt sparks debate over more surveillance,” the Washington online news site The Hill reported on April 22 that, “The number of images snapped of the two suspects reflects deep changes in American society since the Sept. 11, 2001, attacks.”

It added, “Cameras capturing the public’s every move have become much more common and are used for everything from protecting homeland security to ticketing traffic violations such as speeding.”

And, the story notes, “The electronics market research group, IMS Research, estimated that 30 million surveillance cameras have been sold in the United States in the decade after 9/11, including to private homes and businesses.”

New York and Chicago have thousands, and other cities are trying to catch up.

Michael German, senior policy counsel for the ACLU, told the Hill that there were appropriate uses for CCTV cameras in some areas, but “what we don’t want to happen is for millions of innocent Americans to have to be surveilled constantly anytime they go out in public and for the government to maintain databases of those public movements. That doesn’t necessarily improve security.”

In the April 26 New York Daily News, columnist James Warren, in exploring “Surveillance’s dark downside,” said that Americans’ satisfaction at catching the Boston terrorists’ images so quickly should be tempered with the idea that the same cameras “follow us like gum stuck to a shoe.”

Information gathered today — copying licenses plates to catch speeders — can be used tomorrow for totally different purposes. And Warren cites University of Chicago law professor Lior Strahilevitz, who says, “A security system is only as safe as the people who operate it. One has to supervise how people use surveillance data, and that might mean surveilling the people charged with surveillance.”

Remember, there is no expectation of privacy in public. If anyone can see you walking down a street, you can be photographed there, too.

But if you’re in your fenced-in backyard sunbathing when a drone flies over, is that different? You may not know it, but the courts have said, “No,” because if a pilot flying overhead can observe you, so can drones.

Realistically, it’s unlikely we can stop such spying. But we can and should pass strict laws to nail down who uses it and for what purposes — unless we want the word “privacy” to be marked in future dictionaries with this denotation:

“Once common, but now obsolete.” 

M.D. Harmon, a retired journalist and military officer, is a freelance writer and speaker. He can be contacted at:

mdharmoncol@yahoo.com