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Crime Reduction Linked To Lead-Free Gasoline
Hugh Pickens writes "Even low levels of lead can cause brain damage, increasing the likelihood of behavioral and cognitive traits such as impulsivity, aggressiveness, and low IQ that are strongly linked with criminal behavior. The NYTimes has a story on how the phasing out of leaded gasoline starting with the Clean Air Act in 1973 may have led to a 56% drop in violent crime in the US in the 1990s. An economics professor at Amherst College, Jessica Wolpaw Reyes, discovered the connection and wrote a paper comparing the reduction of lead from gasoline between states (PDF) and the reduction of violent crime. She constructed a table linking crime rates in every state to childhood lead exposure in that state 20 or 30 years earlier. If lead poisoning is a factor in the development of criminal behavior, then countries that didn't switch to unleaded fuel until the 1980s, like Britain and Australia, should soon see a dip in crime as the last lead-damaged children outgrow their most violent years."
So does this mean with all the lead paint we are seeing in toys now, we will see another spike in violent behavior.
Interesting - but couldn't this be a correlation != causation issue? Also it seems to imply that violent or criminal behavior is due to organic brain damage. Is that a given?
Of course I haven't read the paper
...Freakonomics correlated the drop in crime rates with the legalization of abortion. Which sounds more sound of a theory to you?
Of course I haven't read the paper In another famous study, the decrease in number of pirates has been linked to global warming...
Bow-ties are cool.
Levitt's book is cited in the first paragraph of the paper, which is very interesting, but rather hard to understand on a (very) brief reading. Essentially, she says that lead contributes 56% to the drop in crime, while the availability of abortions contributes 29%.
Reality is defined by the maddest person in the room
"It couldn't be related to the fact that we have more criminals than ever cooling their heels in prison?"
TFA says that _violent_ crime is down. If there are fewer violent offenders, then how does that explain why the prisons are overfilled? The prison population exploded because we're putting more _nonviolent_ offenders in jail.
Bad troll, no cookie. Try better next time.
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BMO
Personally, I think the most likely cause is one of:
* Reduction in the use of slide rules. With calculators it's easier to get a job as a clerk.
* Increase in CPU speed. Too much time playing games == less time being bad.
* Global warming. It's getting too hot to commit crime.
Engineering is the art of compromise.
Since 1992, approximately six million Americans have been arrested on marijuana charges, a greater number than the entire populations of Alaska, Delaware, the District of Columbia, Montana, North Dakota, South Dakota, Vermont and Wyoming combined. Annual marijuana arrests have more than doubled in that time.
Support NYCountryLawyer RIAA vs People
Roe v. Wade. Reduction in unwanted kids results in less criminals. More abortions for all!
- None can love freedom heartily, but good men; the rest love not freedom, but license. -- John Milton
These statistical correlations are a complete crock. There are a million things that have changed over the last few years that could also be attributed.
One that was done piecemeal (so regression analysis could be performed) and which produced a strong signal under such analysis: Allowing law-abiding citizens to carry concealed weapons for self-protection against criminals. This drastically lowers the overall violent crime and injury/death rates (even if you DO count any crooks shot in self-defense as a "victim").
Interestingly, while many thought it might produce a short bloodbath (until criminals got the message that some of their victims might be armed), that didn't happen. Instead the violent crime rate just dropped, as criminals moved to less-armed areas, switched from muggings, armed robberies, carjackings, "hot" (occupied-dwelling) burglaries, to things like burglarizing UNoccupied homes and stores, or just found legal work. Rapes dropped like a rock, too (though they went up somewhat in nearby areas that hadn't yet liberalized their own laws.)
Turns out the crooks weren't SO stupid that they couldn't see the writing on that wall. And even those who didn't get the message right away usually weren't dumb enough to keep attacking, rather than run away, when they found themselves looking at the wrong end of a pistol.
(When Florida changed to non-discretionary CCW (i.e. the license has to be granted if the applicant jumps through the correct hoops and doesn't have a criminal record), one gang switched to hitting tourist in rental cars, on the assumption they'd be unarmed - both by airport regs and lack of a permit. Florida fixed that by removing the requirement that rental cars have distinctive markings/licenses and by issuing concealed carry permits to tourists. B-) Interestingly, even during the peak of the rob-the-Florida-tourists boom a tourist had less chance of being robbed in Florida than in California.)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
China is taking care of this problem with their usual efficiency, so stop giving them a hard time.
Re:Yet again it bears repeating...
Correlation does not imply causation. While the correlation may be very strong, causation cannot be assumed without ruling out many other potential contributing factors.
How many people have to post this needless gibberish over and over again? Is it some sort of karma whoring?
I mean, the effing SUMMARY got it 100% right:
"Even low levels of lead can cause brain damage, increasing the likelihood of behavioral and cognitive traits such as impulsivity, aggressiveness, and low IQ that are strongly linked with criminal behavior."
We know lead causes brain damage, and we know brain damage can lead to agressiveness, violence, etc.
"The NYTimes has a story on how the phasing out of leaded gasoline starting with the Clean Air Act in 1973 may have led to a 56% drop in violent crime in the US in the 1990s."
Key words: MAY HAVE LED TO. Its a hypothesis. Good.
They aren't asserting causation. They are noting a correlation, and using reasoning to form a hypothesis. So far so good.
An economics professor at Amherst College, Jessica Wolpaw Reyes, discovered the connection and wrote a paper comparing the reduction of lead from gasoline between states (PDF) and the reduction of violent crime. She constructed a table linking crime rates in every state to childhood lead exposure in that state 20 or 30 years earlier.
Documenting the correlation. Even better, its not anecdotal. We're collecting real empirical measurable evidence.
If lead poisoning is a factor in the development of criminal behavior, then countries that didn't switch to unleaded fuel until the 1980s, like Britain and Australia, should soon see a dip in crime as the last lead-damaged children outgrow their most violent years."
A useful prediction? Can it be? Holy shit. Its the full on scientfic method in action. Observe World, Formulate Hypothesis, Test Hypothesis.
I grant that is not the best possible test of the hypothesis, because its not a closed experiment, and its not really repeatable, and a lot of unknowns can get in the way, but we take what we can get. Human-centric sciences like medicine and psychology, or sciences like astrophysics or evolution don't have the luxury of perfect experiments - we can't raise humans in isolated bubbles, nor send a selection of stars into identicale blackholes nor watch a million isolated generations of people --
All we can do in these cases is come up with hypotheses and models, make predictions based on those models to see if we can find examples / counter examples in the observable world.
Overall, its good science here. If the dip in crime occurs where they occur when they predict it, it obviously it won't prove or disprove the hypothesis but it will add significantly to the body of evidence that supports it. If it doesn't occur then we'll have to refine or discard the hypothesis. If ultimately the hypothesis is junk it'll eventually get tossed out. Science is full of wrong hypothesises, but they are the best we have at any given time... that's how it works.
So what exactly do you object to here? That you felt the need to drone about the difference between causation and correlation. It seems everybody involved already got that memo.
In Soviet Russia, our new overlords are belong to all your base.
Reading the article, they already control for abortion, the average crime rate per year, the average crime rate for individual states, and even the effects of people moving from one state to another. The lead level measurements were finer grained than "lead existed before this date, then, everyone stopped using it"- they included state-by-state, year-by-year measurements in their lead data, adjusting for population density (as a surrogate for traffic density).
This was a sophisticated analysis; I wouldn't call it, as some commenters above have, "junk science". It would be surprising for their observed relation to hold, but their interpretation be incorrect. It would be interesting for someone to really come up with an alternative explanation of this paper's observations.
As a side note, I'm pretty sure that by now most lay people, and everyone reading this forum, is aware that correlation does not imply causation. And I'd be willing to guess that the vast majority of scientists have been aware of this elementary statistical fact for some time. It's likely that scientists take many potential influences into account before submitting for publication. So can we please exercise some restraint in the future and actually read the article before denouncing it as "junk science" because, as everyone knows, correlation is not causation? I am emphatically not asking people to take what the researcher says on faith, but if you decry the article without reading it, then your words are essentially noise.
Lead levels in the Roman Empire would be worth a look.
They already were.
Body loads of lead were very high in the later periods - especially among the upper, decision-making, classes. To the point that lead was believed to have been the major cause of a lack of fertility among the upper classes and the decline of those families.
Turns out it wasn't the lead plumbing - where the lead pretty much stayed in the pipes. They had figured out that if you put a lead liner in wine bottles the wine stayed sweet as it aged, rather than turning sour. But that's not because it DOESN'T turn to vinegar - instead the vinegar (acetic acid) reacts with the lead to form lead acetate - which is so sweet it's also called "sugar of lead". And it's REALLY well absorbed by the body.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
"The American people overwhelmingly (not just a majority, but up to 80%) support marijuana criminalization."
From where do you get your stats, besides your arse?
"But more than legalization, I support democracy."
Then you should support the ability of states to decide on their own instead of the use of the commerce clause by the federal government to beat up states that don't toe the line, shouldn't you?
Funny about your use of the word "democracy" there when you actually support federalism. Troll much?
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BMO