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Schneier on SecurityA blog covering security and security technology. « Wholesale Automobile Surveillance Comes to New York City | Main | Friday Squid Blogging: The Word of the Day is "Squid" » August 17, 2007On the Ineffectiveness of Security CamerasInformation from San Francisco public housing developments: The 178 video cameras that keep watch on San Francisco public housing developments have never helped police officers arrest a homicide suspect even though about a quarter of the city's homicides occur on or near public housing property, city officials say. That's not a scarecrow effect. A scarecrow is security theater that works: something that doesn't actually prevent crime, but deters it by scaring off criminals. Mirkarimi is saying that they have the opposite effect; the cameras make victims feel safer than they really are. Posted on August 17, 2007 at 01:25 PM • 30 Comments • View Blog Reactions To receive these entries once a month by e-mail, sign up for the Crypto-Gram Newsletter. Gotta hand it to that Housing Authority. Quite a shock that a governmental agency is performing incompetently. "footage is particularly grainy at night when most crime occurs" Er, install some better lighting? Higher quality cameras? "Nobody monitors the cameras" Yeah, ya might start there. Geniuses. Posted by: Government Solutions Work! at August 17, 2007 01:37 PM Wouldn't better lighting be a cheaper and possibly more effective solution? Posted by: Quilpue at August 17, 2007 01:39 PM Pronouncing security cameras ineffective using this example is like trying to show that legal firearm possesion doesn't deter crime, by putting an unloaded pistol out in the street in front of your house, then getting robbed in your home, and then saying, "See?! Gun ownership doesn't prevent crime!" Security cameras aren't sentient beings. They're tools to be used as a part of a security system, highly effective in the hands of non-morons. Posted by: Government Solutions Work! at August 17, 2007 01:47 PM Scarecrows are effective? Given how uninterested the crows in my neighbourhood are in real live humans, I'd be surprised if any crows were intimidated by some old clothes on a straw dummy. "If men had wings and bore black feathers, few of them would be clever enough to be crows." -Rev.Henry Ward Beecher Posted by: dragonfrog at August 17, 2007 01:51 PM @Gov Solutions Posted by: Quilpue at August 17, 2007 02:14 PM Another analogy would be the fake owls put on roofs to frighten away the pigeons. Within months, the fakes are covered by pigeon droppings. I suspect ordinary criminals are far smarter than birds. Posted by: Roy at August 17, 2007 02:48 PM I'd agree with the scarecrow effect. A stationary scarecrow will eventually become a landing spot for birds. So the farmer may think his crop is safe, when the birds just ignore it. Posted by: Scott at August 17, 2007 03:08 PM How does this compares to the UK ‘big brother’ network of cameras? I seem to remember that it was proven useful in a number of high-profile cases. Was that relevant or just statistical noise? What was different? Posted by: Leandro GFC DUTRA at August 17, 2007 03:09 PM So the question is: is it a problem with the concept of cameras or is it more of an implementation problem? I think it's a bit of both. Posted by: rybolov at August 17, 2007 03:32 PM Cameras are only effective as the security program that implemented them. Judging from this statement, "NOBODY MONITORS THE CAMERAS" it sounds like there is NO program at all. Posted by: community security at August 17, 2007 03:37 PM This is the equivalent of using rot 13 to "encrypt" credit card numbers on an anonymous public ftp site and then claiming that encryption doesn't work when the "encrypted" files are "Decrypted". Its just as easy to screw up physical security as it is to screw up computer security. Posted by: Spider at August 17, 2007 04:01 PM "the cameras make victims feel safer than they really are." This is similar to the fact that nighttime "security lighting" has no effect on crime, and in fact may increase crime. Very interesting to note that the same problem exists with cameras. Have similar studies been performed? As this is presented, it's merely anecdotal evidence, but clearly worthy of deeper investigation. Posted by: William Lee at August 17, 2007 10:48 PM There is little evidence that street cameras reduce the overall frequency of crime and there is evidence that it just moves crime to areas without the cameras (but even then the effect is temporary.) On a very few occasions, the images are useful _after_ the event, which is not much consolation to the victims. Street cameras are possibly the purest form of "security theatre". Big Brother will protect you if you only surrender a little privacy. But you get neither protection nor much remaining privacy. Posted by: Geoff Lane at August 18, 2007 03:51 AM @Leandro GFC DUTRA The UK's network of cameras is useful for catching criminals after the event IF the powers that be can bothered to look through hours of footage. Generally this only happens in the case of more serious crimes. For petty theft - forget it. I don't know of any studies or figures which have analysed their effectiveness. Despite what you may read about the UK being covered in security cameras, it isn't and most people don't really care about them anyway. What's much more high profile in the UK is the use of cameras to catch speeding motorists. These cameras are generally viewed to be: a. Used mainly to generate revenue - the regulations have changed recently and I can't remember who gets to keep the revenue these days. Posted by: John Davies at August 18, 2007 06:30 AM There are a few Dutch cities that have security camera networks and these cameras (and the video registrations they made) have been instrumental in solving crimes. What those cities have is a central control room with people watching the screens and a hot line to law enforcement and ambulance services, so that they can direct the emergency response. I have no statistics, only second hand anecdotal evidence; one of the cases is police catching some rapists "in the act". Do cameras prevent crime? I don't think so. It may be a second order effect from swiping up the petty criminals in the region and moving the pros to other areas. Does a proper camera network help to use police forces more effectively? Yes; I count the cameras as additional eyes that can coordinate the hands. And yes, the recorded video can be used as evidence in court, easing conviction of criminals. There are some hard questions: do the benefits of a camera system warrant the investment? Does it warrant the invasion of privacy? It would help if camera recordings are erased/overwritten after a few days, only keeping the shots that are needed for prosecution of crimes. What's the problem in SFO... If nobody is watching the monitors, you can just as well replace the cameras by mock ups. Posted by: MathFox at August 18, 2007 06:33 AM "Mirkarimi is saying that they have the opposite effect; the cameras make victims feel safer than they really are." Sounds like the situation with painted cross walks which give pedestrians a false sense of safety. Removing those painted cross walks while still allowing crossing has been shown to make pedestrians safer because they know they have to look out for themselves. Posted by: skate at August 18, 2007 03:46 PM @Government, community, "nobody monitors the cameras": Duh. It would be prohibitively expensive if every security camera was monitored, and even more so if you intended to have law enforcement in the vicinity so that they could react to an incident fast enough to make a difference. Most security cameras are intended to scare criminals off because they'll be caught on tape. But that only works if there are procedures in place to review the tapes after an incident, of good enough quality to identify the villain, and with resources available to track down offenders. Posted by: FP at August 18, 2007 04:14 PM The UK network of surveillance cameras has mixed effectiveness. The only benefit of cameras I have experienced is to monitor hotspots in the evenings. In the UK, pubs used to close at 11pm, sending plenty of very drunk, aggressive people on the road. So just the opportunity for a (fist) fight. I have seen very fast police response to fights that were only just starting owing to CCTV. Posted by: Phil at August 18, 2007 06:46 PM Making people feel safer isn't necessarily a bad thing. How safe people feel is often not directly related to how safe they are; statistics on violent crime often trend one direction while surveys on how safe people feel trend the other. This is probably in part caused by the "if it bleeds it leads" mentality of the press. So if putting up some security cameras lets people get on with their lives instead of cowering in fear because the press screamed "DOOOOOOOM", then they serve a valuable public policy purpose. Since the primary objection to them is usually based on government invasion of privacy, not having them actually DOING anything can be a positive thing in that regard. But yes, the best security cameras in terms of security would be ones that actually recorded good pictures that were available to law enforcement in a timely manner. Posted by: syberghost at August 18, 2007 07:33 PM "Making people feel safer isn't necessarily a bad thing." Only if their feeling of insecurity is baseless. Making people feel safe when they are, in fact, in danger is a bad thing and leads to incautious behavior. In such a case, the **false** sense of security can actually make people less safe and the security theater is counter productive and espousal of its value is counterfactual. Posted by: skate at August 19, 2007 12:35 AM (Look in the URL field) A picture I took (in South Africa) at a gas station. Why would one possibly need all those CCTV cameras? I think I counted about 25 cameras in total at that station. And it's not even an area with a lot of crime. I think the owner of the gas station simply has too much money and time on his hands ;-) Posted by: T. Kristoffersen at August 19, 2007 09:17 AM How about hiring Chinese "gold farmers" to watch the cameras? Maybe just those showing movement and with big incentives for reporting a crime fast enough for police response. Posted by: R! at August 20, 2007 01:02 PM Any competent crime reporter knows about these cameras, and knows who can be bribed or coerced to violate his employment contract by providing a copy of anything exciting. I have seen a local TV station (Boston MA) broadcast the video of a capital crime before the investigating detectives had viewed it. -Wang-Lo. Posted by: Wang-Lo at August 20, 2007 02:32 PM @spider How do you do rot13 on numbers? Posted by: TS at August 20, 2007 03:02 PM How wrong you are! You didn't hear any reports of elephants or hyenas committing crimes against humanity in the areas where these cameras were operating did you? Working as intended. Posted by: derf at August 21, 2007 04:54 PM I would name the Opposite of SCARECROW effect as The FENCE-POLE effect. Part of the fence is installed, and the by-standers think that the fence is complete when it doesn't extend far enough to deter the bull on one side from going around it, (or through it!), and does nothing to slow down the rattlesnakes. Sort of like Jurassic Park with the power turned off. Posted by: Peter E Retep at August 23, 2007 05:07 PM "apoplectic", Seriously, she accused them of having stroke like symptoms? I'm pretty sure this is a misprint. Posted by: Chip Thomas at August 24, 2007 12:37 PM We had cameras that could take photos of you running a red light, there were about three lenses behind armored glass, probably a camera for daylight, one for infrar red and and an exray to see if you have things in your pocket. to see the future of law enforcemnent, go to the movie "minority report" Posted by: carbon14 at May 7, 2008 08:33 AM Post a comment
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