London's public cameras can't solve crimes

For years groups like the ACLU have been fighting to restrict the use of surveillance cameras in public placesâ''itâ''s bad enough to be caught on film every time you use an ATM or buy a convenience store hot dogâ''and they've been slow to catch on. Across the pond, however, the United Kingdom has embraced the technology, setting up more than 10,000 cameras in London alone.

But if you're planning a British crime caper, don't despair: having more cameras in an area seems to have no effect on how many cases the police actually solve there. The Liberal Democrats of the London Assembly published their proof this week, which they acquired through a Freedom of Information Act, according to Theyâ''re clearly trying to paint the camera systems as a waste of money that provides minimal results.

With a quick look at the new crime data, their conclusion seems hard to argue with: whether boroughs had a few dozen cameras or a few hundred, they all solved only about 20 percent of the crimes reported.

But the straightforward numbers can be a bit misleading. As it turns out, researchers have struggled for years to determine if and how cameras work.

Temporarily setting aside any Orwellian fears, itâ''s easy to see why cameras should reduce crime in theory:

1) They make it easier to apprehend and prosecute criminals who are caught on tape (which the Fox network will eventually turn into television specials).


2)They act as a deterrent (this is why stores install fake security cameras and dad's lie about urine-detecting pool chemicals)

This new data seems to rule out the first, as 80 percent of crimes reported still go unresolved even in densely recorded areas. So what about prevention? A 2005 report [PDF] commissioned by Britainâ''s Home Office, found that installing cameras reduced crime in only one of the fourteen closed-circuit systems that researchers studied. Strike two.

But not so fastâ''according to a 2005 review of closed-circuit video cameras and crime, most studies show that such systems do manage to reduce crime. So why can't analysts figure out if they work or not?

The discrepancy arises because crime statistics almost inevitably bundle many variables into one number. In the 2005 Home Office Report, the authors note that crime rates may have gone up in some areas simply because the surveillance systems recorded crimes that would have otherwise gone unreported. Similarly, individuals might be more likely to report crimes if they suspect there's video evidence backing them up.

Regardless of these factors that may suppress the statistical success of video surveillance, the fact that there's still so much debate means that they aren't revolutionizing law enforcement. Even with continued technological improvement, there's a chance that Big Brother just doesn't work.


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