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LAPD Police Claim Helicopters Stop Crimes Before They Happen
HughPickens.com writes True Angelenos don't even bother to look up when one of the LAPD's 17 helicopters rattles their windows searching for a car-jacked Camry or an assault suspect hiding under a jacaranda but few doubt that more bad guys would get away without the nation's largest police helicopter fleet to help chase them. Now the LA Times reports that data shows that LA's helicopters are stopping crimes before they happen. Tapping into the data-driven policing trend, the department uses heat maps, technology and years of statistics to identify crime "hot spots." Pilots then use their downtime to fly over them, on the theory that would-be criminals tend to rethink their nefarious plans when there's "ghetto birds," as Ice Cube calls them, hovering overhead [explanatory video with annoying sound]. Months of data show that the number of serious crimes reported in the LAPD's Newton Division in South L.A. fell during weeks when the helicopters conducted more flights. During the week of Sept. 13, when the helicopter unit flew over Newton 65 times, the division recorded 90 crimes. A week later, the number of flights dropped to 40 and the number of reported crimes skyrocketed to 136, with rises seen among almost all types of crime, including burglary, car theft and thefts from vehicles. "It's extremely cutting edge," says Capt. Gary Walters, who heads the LAPD's air support unit. "It's different. It's nothing that we've ever done before with this specificity."
But Professor Geoffrey Alpert. a policing expert who has studied the use of police helicopters in Miami and Baltimore, says the choppers can deter crime in the short-term but criminals will likely return when they're not around (PDF). "You are deterring the criminals but you aren't getting rid of them and their intent. Those criminals could strike in a different time and place," says Alpert. "I mean that's the whole thing about random patrol. You see a police car and it's the same thing. You hide, he goes around the block and you go back to your breaking and entering."
But Professor Geoffrey Alpert. a policing expert who has studied the use of police helicopters in Miami and Baltimore, says the choppers can deter crime in the short-term but criminals will likely return when they're not around (PDF). "You are deterring the criminals but you aren't getting rid of them and their intent. Those criminals could strike in a different time and place," says Alpert. "I mean that's the whole thing about random patrol. You see a police car and it's the same thing. You hide, he goes around the block and you go back to your breaking and entering."
Drones could broadcast helicopter sounds.
So criminals will wait until the police pass by before committing a crime. Pretty obvious. .
Except that it is not "obvious". Most crime is opportunistic. Take away the opportunity, and you take away the crime. Criminals do not operate on a "quota system". The additional flights lowered crime over the entire period measured, so there is no evidence that criminals were just waiting for the helicopters to pass by.
If you eliminated police entirely, reports of crime would *certainly* go down. If police simply stopped responding to calls, reports of crime would certainly go down.
This is my problem with concluding that choppers deter crime from police crime statistics; while it seems plausible, "reports of crime" are just an approximate proxy for "incidence of crime". Gaming this has been an unfortunate consequence of "data driven" approaches to policing (see Campell's Law).
Which is not to say that helicopters don't deter crime. It seems perfectly plausible. But it's also possible they cause crime to move elsewhere, timeshift ,or take forms which are harder to spot.
This gets to how you use data effectively for anything. When something in the data jumps out at you, it's tempting to believe your initial interpretation of it because it's so compellingly satisfying. But what you really need to do is *test* that interpretation, beat on it as hard as you can. If it can stand up to that you really have something. There's a world of difference between "promising" and "conclusive".
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In the far distance a helicopter skimmed down between the roofs, hovered for an instant like a bluebottle, and darted away again with a curving flight. It was the police patrol, snooping into people's windows.
-- 1984, George Orwell
XML is a known as a key material required to create SMD: Software of Mass Destruction
The 'peaceful enjoyment of liberty' of hundreds of innocent citizens is being infringed to prevent a few car break-ins.
These copters are LOUD. And in these 'pre-crime' patrols, they make liberal use of their spotlight, essentially treating ordinary citizens as criminal suspects. They even invade Santa Monica (independently incorporated city), circling endlessly for 3 hours at a stretch in the middle the night, depriving entire neighborhoods'-worth of a restful night of sleep.
Oh, the best part, was on a radio interview show: The LAPD guy justified the practice on economic grounds! Wah, we just don''t have enough officers to patrol... Really? How much does a helicopter cost to operate? Maybe $300-500 per hour? Plus the two pigs along for the ride are getting salary. Could that money not be spent on neighborhood patrols on foot, or at least in squad cars?
It's ridiculous.