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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."
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
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.
"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
I think you need to be exposed to actual lead, not just xenophobic media hysteria about lead.
except that they found a much better correlation than any of these that they considered interesting. They didn't say "hey! no more lead in gasoline and crime went down. Yippeee!" as you're making it out to be. If you don't believe me, try to publish your CPU speed theory. Much of science boils down to the careful study of correlation.
If you want to bash their study, fine, but at least RTFP, not just the summary on slashdot.
"Question with boldness even the existence of a god." - Thomas Jefferson
The Scientific Method:
.... but that's the whole point. That's what makes this real science - somebody sticking his neck out in public, opening himself to the possibility of being wrong.
i) Observation
ii) Theory
iii) Prediction
iv) Experiment
In THAT order.
An awful lot of "science" these days seems to forget about the last two items - and they're the most important.
Will the prediction turn out to be true? Who knows
No sig today...
However, in this case, there was a direct correlation of time as well. Everything you listed happened in all the studied areas around the same time - and were they related to violent crime, the drop in violent crime would happen around the same time in all of these locations, which it didn't.
* Slide Rule and CPUs: This would show a marked drop which could be mapped by time and income bracket (as these would be the two factors mandating uptake), and not geographic region by state.
* Global warming: This would show a marked drop which could be mapped by latitude, proximity to large bodies of water, and time, as these would all be mitigating/exaggerating factors in the relevant changes.
Find correlations with these factors, and maybe one of your theories can be tested. (and actually, global warming might be a good one - too much heat means more agitated people at lower latitudes, more happy people at higher latitudes, if we take the theory that crime to be inversely proportionate to happiness).
Occams razor people - this correlation works because it is one of the simpler explanations that fits what happened. Additionally, a testable prediction has been made from it - in 10-15 years, the theory will be tested.
34486853790
Connection too slow for X forwarding? Try "ssh -CX user@host"
Actually, the paper makes an minor reference to lead-based paint. Their representation is that the absorption mechanism is less effective - it requires consumption of paint chips.
As a previous poster represented, inhalation of exhaust is a very efficient vector. Also, there is contact with materials on which exhaust is deposited - soils and water. Like pesticides (or nuclear waste, for that matter), a widespread low-level exposure is all that is necessary if total dosage characteristics come into play. An organism living continually exposed to low levels of a toxin that has cumulative effects may not be noticeably damaged immediately, but it will eventually manifest.
The little guy just ain't getting it, is he?
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.
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.
A 1970 Challenger with almost 400 horsepower was about $25K in today's dollars. $25K today gets you something like a WRX or Mazdaspeed 3, which will absolutely _crush_ that car in anything but a straight line, and on period correct tires will also beat it in a straight line. C'mon, aside from missing that V8 engine noise, we're living in a golden age.
"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
Yet despite a 56% reduction in violent crime, we increased our prison population faster than we increased the national population and have a record level of people in jail. How does unleaded gas explain that?
Perhaps it's that mandatory sentencing laws for drug crimes and 3 strikes laws took a lot of violent offenders and potential violent offenders off the street, rather than less lead.
Start a happiness pandemic
"Perhaps, but unless you can compare places with those legal features with places that don't and show there's a difference, you don't have a very impressive argument."
Yes, but finding a causal relationship between lowered crime and more people spending more time in prison is easier than finding it between lowered crime and lowered lead.
The economy in the 90s was better than in the 70s. Remember how bad inflation was under Carter? You can tie lower crime rates to a better economy (more people with jobs, more people with hope, less idle hands for the devil's work).
I'm not saying any one thing led to it. I'm just saying that you can tie a drop in crime in the 90s to a lot of things. There are more compelling theories than lead, IMO.
Start a happiness pandemic