Comment by JangoSteve | Hacker News Reader

Comment by JangoSteve | Hacker News Reader

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EDIT 2: Hmm, maybe I shouldn't have removed my original response, I just didn't want to derail the conversation upon second thought. For posterity's sake, my original response was something along the lines of this:

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I think you may be overestimating the effects of "the greater security picture" involving community, observant neighbors, other monitoring systems for the average community. For example, my first startup was RateMyStudentRental.com, and as I recall adding automated motion-activated sensors and lighting actually had a negative effect on break-in protection. As in, adding such a system actually increased your chances of having a break-in. According to the study, neighbors don't actually pay much attention to someone standing at a well-lit door (mileage varying based on the specific community obviously).

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ORIGINAL EDIT: I won't comment on the technicality of the differences between the analogous situation and the actual situation at hand; the differences have nothing to do with the point being made. Don't get caught up in the analogy, because it's just an analogy.

In case it wasn't clear the first time around, the entire point of the analogy was that, breaking into and vandalizing someone's business just to show them that it can be done is generally a bad idea. Though I don't think anyone would argue it isn't effective.

> [...] automated lighting systems actually have a negative effect on break-in protection [...]

Do you have a source for this? I've always been under the commonly held impression that this has a preventative effect, and it would be very interesting if the opposite really is true.

Good question. It was a long time ago, and I'm having trouble googling for it, because all I get in search results are articles and how-tos by motion-sensor companies selling their products. I'll search though and update if I find it.

UPDATE: Hey, awesome, turns out we blogged about it back in the day: http://blog.ratemystudentrental.com/2008/03/05/a-safe-home-i...

Here is the original article: http://www.schneier.com/blog/archives/2007/09/light_and_crim...

Much so-called security lighting is designed with little thought for how eyes -- or criminals -- operate. Marcus Felson, a professor at the School of Criminal Justice at Rutgers University, has concluded that lighting is effective in preventing crime mainly if it enables people to notice criminal activity as it's taking place, and if it doesn't help criminals to see what they're doing. Bright, unshielded floodlights -- one of the most common types of outdoor security lighting in the country -- often fail on both counts, as do all-night lights installed on isolated structures or on parts of buildings that can't be observed by passersby (such as back doors). A burglar who is forced to use a flashlight, or whose movement triggers a security light controlled by an infrared motion sensor, is much more likely to be spotted than one whose presence is masked by the blinding glare of a poorly placed metal halide "wall pack." In the early seventies, the public-school system in San Antonio, Texas, began leaving many of its school buildings, parking lots, and other property dark at night and found that the no-lights policy not only reduced energy costs but also dramatically cut vandalism.

I remembered it incorrectly, as apparently motion-activated lighting helps, but on-all-night floodlighting makes the situation worse.

Peter Gutmann reported some interesting studies in his keynote talk at Shmoocon this year. It's probably available on Ustream or the Shmoocon site.

In short, sometimes darkness helps. Consider a tall glass office building. If all the lights are out, nothing stands out to a security guard more than a flashlight waving around in the darkness.

Hey Steve! Good to see another Kettering grad on here :)

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