Proposed Biological Explanations For Historical Trends In Crime

My debate on crime rates with Michael Anissimov has been long and meandering, but I think we’re starting to come to something of a consensus. I think (I don’t know if Michael agrees) that the evidence showing long-term decline in crime from the Middle Ages to the Industrial Revolution is pretty good. There’s also irrefutable evidence showing decline in crime from about 1985 to the present. That leaves a gap from about 1850 to 1980.

I previously asserted crime was stable during that period, pointing out similar murder rates between 1850 New York and London and 1980 New York and London, which I trusted more than (say) burglary rates. But Michael replied with a 2002 study showing that improved medical technology has saved a lot of murder victims and bumped their attackers’ crimes down to attempted murder, meaning the apparent murder rate is artificially low. Correct that, and murder could have increased by 5-10x or more from 1850 to 1980, which would not be too different from the rates in lesser crimes like burglary.

I am still not entirely certain about this. We have good records on attempted murders for the past 30 years or so, and they have been going down along with the murder rate. And it is surprising that the improvement in medical technology so perfectly balances out the increase in violence. But it’s a strong study, and so I will provisionally accept that crime including murder could have risen by 5-10x or more from 1850 to 1980.

But we don’t have to accept that the reason is too much democracy or some sort of wacky political point like that.

I have previously come out as a biodeterminist. I suspect most social influences matter less than anyone thinks and most biological influences matter more than anyone thinks. When I say that, everyone always assumes I’m talking about genes, which is too bad because genes are almost the least interesting aspect of biodeterminism.

Anyone reading this blog probably already knows that lead is very strongly suspected of causing crime. A generation after gasoline was leaded, crime increased by a factor of four; a generation after lead was banned from gasoline, crime decreased by a factor of four. Levels of automobile lead emissions were found to explain 90% of the variability in violent crime in America. States that banned lead more quickly saw crime drop more quickly. Neighborhoods with higher lead levels consistently had higher crime rates. Blood lead levels show a marked inverse correlation with IQ, and a marked direct correlation with criminal history, even when plausible confounders are taken into account. And neuroscientists have known for decades that lead damages parts of the brain normally involved in good decision-making and in impulse control.

Lead levels started rising with the Industrial Revolution and, although in decline, are still far higher than in pre-industrial societies. They are highest in cities and especially in the inner city. They have shown correlation with crime, teenage pregnancy, and many mental disorders.

But like I said, everyone reading this blog probably already knows that. So let me talk about something I just learned last week.

Omega-6 fatty acids.

These are some of those “polyunsaturated fatty acid” things you always hear nutrition geeks talking about. They were pretty rare in human diets until the advent of industrial food processing. Here is a mysterious graph for which I have no source:

Here’s another that comes from Stephan Guyenet:

So suffice it to say that our consumption of these fatty acids has increased a lot. This is not surprising – they are most common in things like the vegetable oil that a bunch of preserved foods have.

The other main kind of polyunsaturated fatty acid, omega-3, is mostly found in seafood and is the main component of the infamous “fish oil”. It hasn’t increased very much at all and so most people have an abnormally high omega-6:omega-3 ratio compared to the past and to the environment of evolutionary adaptedness.

Omega-3 and omega-6 fatty acids are important for cell membrane fluidity, especially in the brain where they affect neurotransmitter receptors and other neural functions. If there are the wrong amounts of them, this would very plausibly derange various cognitive functions.

So let’s look at Joseph Hibbeln’s paper Seafood Consumption and Homicide Mortality.

The Guardian describes it like so: “Hibbeln and his colleagues have mapped the growth in consumption of omega-6 fatty acids from seed oils in 38 countries since the 1960s against the rise in murder rates over the same period. In all cases there is an unnerving match. As omega-6 goes up, so do homicides in a linear progression. Industrial societies where omega-3 consumption has remained high and omega-6 low because people eat fish, such as Japan, have low rates of murder and depression.”

From Stephen Guyenet’s excellent post Vegetable Oil and Homicide:

I know, I know, it’s a nice pretty line, but where are the randomized controlled trials?

To which one answers: “in dozens of different countries around the world”. One of the most famous is Gesch et al 2002, which gave dietary supplements including fish oil or placebo to 231 prisoners and found a 25% drop in prison violence (p = 0.03) using intention to treat and 35% (p = .001) using completers. A replication study on 231 Dutch prisoners found almost exactly the same results. Another study of 468 schoolchildren also showed exactly the same results. And…actually, I’m just going to quote from Anatomy of Violence: The Biological Roots of Crime, a book I just found on Google and have suddenly conceived a burning desire to own:

In Australia, six weeks of omega-3 supplementaion reduced externalizing behavior problems in juveniles with bipolar disorder. In Italy, normal adults taking omega-3 for five weeks showed a significant reduction in aggression compared to controls. In Japan, a randomized controlled trial found that ADHD children with oppositional definat disorder showed a 36% reduction in their oppositional behavior after fifteen weeks of omega-3. In Thailand, a randomized double-blind trial of the omega-3 fatty acid DHA resulted in a significant reduction in aggression in adult university workers. In the United States, women with borderline personality disorder randomized into supplementation of the fatty acid EPA for two months showed a significant reduction in aggression. Another American study, this time a four-month randomized double-blind placebo-controlled trial of fatty acid supplementation in fifty children, showed a significant 42.7% reduction in conduct-disorder problems.

We have been burned by omega-3 before. Every couple of weeks someone makes an exciting claim about it, and a few weeks later it is shown to be false or overblown. A big government review of the research on mental health basically dismisses everything done thus far as insufficient to draw meaningful conclusions. But I am hopeful.

I will add one more chemical, one of my favorites. Lithium. Many studies (1, 2, 3 find strong (that last one is p = .00003) links between lithium levels in the water supply and an endpoint crime or suicide. Lithium is a known neuroprotective agent, is probably at least calming, and may be otherwise good for the brain.

I am not certain of this, but I have heard from a few sources that modern water treatment/purification removes most minerals, which would suggest we are getting much less lithium than people in the old days who got their water from a well or whatever.

So we are likely getting more lead, more omega-6 (and relatively less omega-3), and less lithium than people in 1850. If there has been an increase in crime and other undesirable/impulsive behaviors, I think these biological insults are at least as worthy of examination as political changes that have occurred during that time.

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70 Responses to Proposed Biological Explanations For Historical Trends In Crime

  1. Andy says:

    This does raise the specter of the Cathedral injecting Omega-3 into everyone’s meals morning, noon, and night…

    Actually, that would make an interesting spec-fic story…

    • Scott Alexander says:

      Working on it!

      (I would actually totally support that proposal so much)

      • Sam says:

        Considering how large (much larger than it was before the industrial revolution) and diverse the human population is, I’m sure some people would be more sensitive than others. Adults, children, pregnant women, the elderly, the sick and even animals would all be getting the same dose in their water. It also goes against informed consent. I’m shocked that anyone would support adding drugs to the water supply, especially when it’s just to make people more calm. Right in the first few lines of that article it mentions Aldous Huxley’s soma, Brave New World was about a dystopia.

        • nydwracu says:

          One word: iodine.

        • Scott Alexander says:

          What are your thoughts on fluoridation, then?

          I may have had an abnormal reaction to Brave New World. At the part where Mustapha Mond argued that discontents were fighting for the “right” to grow old and ugly and get syphilis and have too little to eat and live in constant apprehension and be tortured, I mostly thought “Oh, yeah, guy has a point. No wonder they made him World Controller. I know dystopias don’t let you vote, but if they did I would re-elect him.”

    • jrayhawk says:

      DHA (and to a lesser extent EPA) is used in axonal and marine tissue applications specifically because it is extremely mechanically flexible (a rare quality at ocean temperatures), having six cis bends. Unfortunately all those cis bends are *desaturations* which means it is *extremely* vulnerable to oxidative stress. This is normally mitigated by having it packaged in an actively maintained matrix of stable fats and freely available antioxidants in the form of a sea creature.

      So, given that, even in the form of a fish, it goes bad in a low number of months in the freezer, a low number of days in the fridge, and a some number of hours at room temperature, how would fortification or supplementation work? Oxygen-free processing and packaging? Is that likely to be less expensive than just recommending seafood?

      (Not that the cathedral has historically cared about pathologies introduced by its naive diet enrichment plans. See: folic acid.)

      • Andy says:

        I came up with an answer for this:
        RELIGION!
        Omega-3 supplements every day as part of ritual, a la Communion wafers.
        Also, fish isn’t the only source of omega-3, just the most widely known, as far as I can tell. Flax seeds, walnuts, and soybeans also contain fair amounts.

  2. “I suspect most social influences matter less than anyone thinks and most biological influences matter more than anyone thinks.”

    I’m puzzled by this statement. I think biology matters a lot, so possibly we don’t disagree much and I’m mostly just seeing rhetorical flair… but OTOH while I don’t think “social influences” are magic pixie dust you can sprinkle on people to get them to do whatever you want, I think people are pretty decent at responding roughly rationally to different societal circumstances, and there’s room for different societies to reach different stable or stable-ish equillibria.

    • Scott Alexander says:

      I agree it’s not a very specific claim, but three things I particularly think of when I say this are:

      – Nurture Assumption’s thesis that parenting doesn’t really matter for kids
      – Consistent finding that psychotherapies are probably just very specific and effective kind of placebo
      – Failure of things in the general category of public awareness campaigns

      Unfortunately my brain has a category of things called “social influences” which is hard to define – for example, I wouldn’t include monetary incentives or even some forms of status-seeking in it. I admit that this makes me sound like I’m making a much stronger claim than I am.

      • Paul Torek says:

        Sure, parenting doesn’t matter – if you ignore the fact that parents can exert a decisive influence on peer groups, which were found to matter a lot.

        As for psychotherapy, whaaaa? “RESULTS:

        Compared with placebo, the combination of fluoxetine with CBT was statistically significant (P =.001) on the Children’s Depression Rating Scale-Revised. Compared with fluoxetine alone (P =.02) and CBT alone (P =.01), treatment of fluoxetine with CBT was superior. Fluoxetine alone is a superior treatment to CBT alone (P =.01). Rates of response for fluoxetine with CBT were 71.0% (95% confidence interval [CI], 62%-80%); fluoxetine alone, 60.6% (95% CI, 51%-70%); CBT alone, 43.2% (95% CI, 34%-52%); and placebo, 34.8% (95% CI, 26%-44%).” Says the top google hit for a “CBT prozac placebo” search, Silva et. al., pubmed

        • Scott Alexander says:

          See https://slatestarcodex.com/2013/09/19/scientific-freud/ . Psychotherapy works, but it may be a very special kind of placeboish type thing.

        • Paul Torek says:

          I don’t think “having a charismatic, caring person listen to your problems” counts as “placebo”, although some of your standard placebo effect is probably accounted for by caring. I guess that’s what makes it placebo-“ish”? Regarding Freudian psychotherapy, one should consider the alternative hypothesis that regardless of formal training, after a few months/years all therapists wind up doing (roughly) what works.

        • Anthony says:

          Suggestion for testing the hypothesis of therapy-as-placebo: Priestly counseling, and fluoxetine+priest. Try this in both the U.S. and in a place with stronger religious belief (if I were on the research team, I’d suggest rural Colombia because I have contacts, but lots of places would work.)

      • a person says:

        I think sort of what you’re saying is that on a large scale people telling other people to do stuff is not very likely to have a major effect.

    • Valhar2000 says:

      You are putting the words “people” and “rationally” in the same sentence. Terrible, terrible mistake.

      • I’m well aware of how irrational people can be, but here I’m talking in the sense of, as Scott once said, “most people are rational enough for their own purposes.” Like, they may have crazy beliefs in the abstract but when it comes to looking after their own interests, they do pretty well.

  3. Gunlord says:

    Yet another thought-provoking post. You’re on a roll today, Scott. Here’s something to ponder: Is there any way to cross reference these various nutrients (omega 3, lithium, etc.) with regards to different regional diets? I’m particularly interested in how this intersects with race. Neoreactionaries often claim that blacks are disproportionately crime-prone due to genetics, but I wonder if a lack of nutrients in the sort of food eaten by the most crime-prone segments of the black population might affect, to at least some extent, those unhappy statistics.

    • Valhar2000 says:

      Well, stereotypically, black people live in poor inner city areas, and there’s not much seafood to be found there; so, they would be prime candidates for these effects.

      It would be interesting to find populations of poor inner city African Americans who do have ready access to seafood (does New Orleans fit the bill?), and compare crime rates.

      • ziel says:

        New Orleans? That would certainly falsify the theory – though just because it’s on the Gulf doesn’t mean its residents have higher than typical consumption of Omega-3’s.

        • Randy M says:

          I suspect in creole cuisine, any gains from eating seafood are lots in eating fried food.

        • Andy says:

          There’s also the “food desert” phenomenon, where inner-city people have less acess to nutritious food. I do wonder whether omega-3 is on e of the nutrients tht gets left out. Though most research has focused on fruits and vegetables.

        • Damien says:

          Kevin Drum called out New Orleans as being still coated in lead, so that might overwhelm any dietary contribution.

    • Damien says:

      One thing I’ve wondered about is genetic variability in being able to process the Western diet. Lactase persistence is the big obvious one, but with all these wheat sensitivities even among Europeans, I wonder about people whose ancestors didn’t grow up on it. Of course, most African-Americans are part white, but still. Conversely, all these New World foods… If anyone ever showed what looked like a strong genetic case for racial differences in intelligence, it might be that what they found was differences based on the common diet, with some races less able to get optimal nutrition from it.

      Relatedly, non-Japanese eating the Japanese diet might not get the same longevity benefit.

      That could be a practical argument for avoiding race mixing: scrambling genes together could make your optimal diet hard to determine, or even non-existent if there’s conflicting genes. Of course, mixing also boosts your disease resistance.

  4. BenSix says:

    Interesting. At the risk of confirming stereotypes about Internet debates and the appearance of Israel, it would make a good test for the theory.

  5. Julia says:

    This is why the dietician at the jail where I work wanted to send all the prisoners home with a suitcase of fish oil pills upon release. Until they eliminated his position.

    • Scott Alexander says:

      On a graph of my short-scale emotional state today, this comment would be represented by a moderate-sized spike of happiness and optimism followed by a huge drop.

  6. Randy M says:

    Theodore Dalrymple, a British prison doctor, has written on the wretched diet of the British lower class, in but especially out of prison. See for example:
    http://www.city-journal.org/html/12_4_oh_to_be.html

    • Thanks for the link, though I could do without the liberal-bashing. It’s not as though conservatives are doing anything effective about the problem, either.

      • Randy M says:

        Doing nothing>Ineffectual efforts>counterproductive efforts

        • Andy says:

          Ineffectual or counterproductive efforts>doing nothing
          Because you ineffectual or counterproductive efforts at least raise the possibility, however slim, of realizing that you’re doing something wrong, then eliminating a possible solution from the list, and possibly, by process of elimination and trying different things, you arrive at a working solution.

        • Prussian Prince of Automata says:

          A wise woman once said;

          “Don’t just do something, stand there!”

          It’s a lot easier to jump on the first idea which comes to mind than to put in the time and really think it through, because thinking is hard at the best of times and anxiety grinds away at you the longer a problem doesn’t present an immediate solution. Think about the people who die in the desert because they leave their car and go wandering off into the unknown out of a misguided notion that they ought to be doing something to save themselves; had they merely stayed put, rescuers could have found them easily.

          Wise people often appear passive for exactly the same reason; fools are constantly running around and exerting themselves uselessly for a vain hope of achieving their goal, but someone who knows the right time to act will wait and conserve their strength until action is called for. Trial and error has it’s place, but it’s a wasteful policy in most cases.

          Edit: Added source of quote, corrected my misidentification of her sex. Also removed a repitition in the desert analogy.

  7. James Babcock says:

    One of the really horrible things is, Omega-3 and Omega-6 content don’t appear on nutrition facts labels; they’re merged together into “polyunsaturated fat”, which is useless. I strongly suspect that this is a big part of why it took so long for people to notice the problem.

    • Scott Alexander says:

      Is it very hard to figure it out? I mostly assume that on anything preprocessed or not-fish that doesn’t boast of its omega-3 content on the label, PUFA means omega-6.

      • Mike Blume says:

        My (very weak!) understanding is that land animal fats sometimes have plenty of omega-3 but this is a function of the animal’s diet, hence all the fuss about grass-fed butter/beef.

        • Tom says:

          Some non-fish sources produce ALA instead of the desirable EPA or DHA which is converted by the body at a low rate of 10-15% to the more desirable form. Despite this, they’re still marketed as the same as fish oil. Source, but it’s only talking about vegetarian alternatives for sources. I’m can’t find anything saying whether this extends to other animal sources.

  8. B says:

    Something that always fascinates me about this arguing about crime rates is – why are the reporting data from police trusted so much?

    I regularly stumble upon reports (sorry, no links at hand, so caveat lector) of police & sheriff dep’ts “sanitizing” crime data on an amazing scale, mostly driven by the data needs from the top of the department, and then – nothing comes of it as far as the debate is concerned.

    To me it seems that it’s one of the cases where an input falls out of a debate because it fits nobody’s story (left side wants to trivialize chaos, right wants to worship authority & police).

    • Douglas Knight says:

      That’s why we focus on murder rates.

      • B says:

        I really need to keep those articles around when I stumble upon them in the future, but murder as the “hardest to explain away” crime has seen better days according to my recollection. The articles I remember but cannot provide (which is the next best excuse right after “cheque’s in the mail”, I realize) specifically had some fascinating shenanigans around murder, such as:

        • Avoiding getting charges upgraded when victims die of their injuries significantly later by explaining them away to complications from treatment etc (NYC IIRC).
        • “Believing” ludicrous explanations how “accidents” happened (Don’t remember where, even vaguely).
        • Just pretty much ignoring rumors of bodies lying around in a ditch. This low is reserved for the most dysfunctional areas with the strongest “stop snitching” ethos where the deniability is plausible, I think the story was from somewhere in Michigan, not Detroit though.

        In short, you don’t have to explain away the body, just the foul play leading to death.

        (Only slightly related, but I wanted to get it off my chest since I’ve been thinking about it for a while: What I believe is still important, but by far not as much as often claimed around my echo chamber (I’m from the NRx niche, mostly) is how much better trauma treatment has gotten. Around the same time, the weaponry commonly used by criminals (high-capacity handguns, cheap stamped SMGs) also became a lot more deadly; not necessarily for intended victims, but especially for bystanders. 9mm may not have that much immediate stopping power, but it sure is deadly. More spray also means more collateral damage per intended kill, or at least almost a guarantee that somebody gets hit.)

        Edit – empty lines for paragraph separation do work, just not in the preview.

        • Douglas Knight says:

          There’s a margin of error in everything. Is this source of error larger than other sources of error? Is it big enough to have a reasonable chance reverse the order of murder rates in Japan < Western Europe < America ? Big enough to change the secular trends in Canada and the US of doubling of murder rate 1965-1975, halving 1975-2005? I have not heard reports of police sanitizing homicide reports on a relevant scale. I would be very interested in seeing such reports, but it doesn't sound like you have seen any, either.

          In theory, there are multiple sources of statistics. Murders known to police can be compared to murders known to coroners. They talk to each other, but the coroner also talks to doctors and is not going to simply let the police put the blame on the doctors. If the coroners measured significantly different murder rates than the police, I think I'd have hear about it. You can check the hypothesis that “accidents” or suicide have displayed homicide. Tell me what you find. In theory the government might notice the disappearance of large numbers of people in ditches, but I don’t think I would hear if they did.

          I have heard the claim that professionals are suspicious of pre-1960 murder data.

    • Damien says:

      Police reports *aren’t* totally trusted, so we use crime/victim surveys as well.
      https://en.wikipedia.org/wiki/Crime_statistics

      Also, for tracking trends, you don’t need the numbers to be precisely accurate, you just need them to have constant bias over time. Failing that, monotonic bias: a department might work harder to cover up a higher crime rate in their reports, but there’s a good chance it would still go up. On the flip side, it’s not clear what the bias would be: exaggerating the crime rate might get more money or protect police jobs.

      As for homicide, another benefit is that the definition varies less over time and country; dead people are dead people, unlike assault or rape. It also has some use for guessing at homicide rates in the past based on bones.

  9. Doug S. says:

    IIRC, lithium’s effects on bipolar disorder were discovered because some areas had high levels of lithium in drinking water…

  10. Luke G. says:

    Just a note of interest: even Taiwan experienced a spike in violent crime as recently as the late 90s:

    “Taiwan has become a cosmopolitan and mobile society, but also — by its own standards — a dangerous one.

    Indeed, crime rates are creeping up and in some cases surpassing those in Western countries; the murder rate in Taiwan is 8.5 per 100,000 people, compared with 8.2 in the United States in 1995.

    ”The perception of the people is right,” said Huang Fu-yuan, a criminologist at Central Police University. ”Crime is terrible.”

    ”We need to pay the price of modernization,” he added. ”If we are going to get more materialistic, then there will be more crime.”

    Over all, crime rates soared 80 percent over the last decade in Taiwan, but public discontent exploded in May after several particularly brutal cases, including the kidnapping and slaying of Pai Hsiao-yen, the 17-year-old daughter of a beloved movie actress.”

    http://www.nytimes.com/1997/07/14/world/crime-invades-a-once-peaceful-place.html

    Also note that Taiwan is an ethnically homogeneous society, yet its homicide rate at the time surpassed America’s, despite having no significant population of Black people. I mention this because I know lots of right-wingers like to blame America’s crime figures on Blacks and ethnic diversity.

    • Douglas Knight says:

      Here’s 20 years of Taiwanese murder rate, 1993-2012. It’s a lot higher than other rich Asian countries, but your choice of year is cherry-picking.

      People don’t say that blacks make whites more violent, they look at rates broken down by race! The generally accepted numbers are that half of American murders are by whites and half are by blacks. American whites murder at about the same rate as Taiwanese, a much higher rate than Western Europeans or other rich Asians.

  11. Anonymous says:

    Michael’s point about modern medicine is a good one – and a subtle way in which technological progress can mask social decline.

    Another important consideration is that the modern crime rate is in the context of significantly higher incarceration rates (PDF) and unprecedented expenditure in guard labor. Add to the ledger the hard-to-define but enormous sum of money individuals spend to physically separate themselves from loci of crime. This manifests in clunky things like gated communities as well as more subtle things like moving to the suburbs for “good schools” and higher real estate costs in cities since a lot of otherwise-desirable properties are considered unsafe. I wouldn’t claim the *entirety* of positional expenditures in real estate under the heading of “cocooning costs,” since part of it is the positive desire to be around other cool people, but certainly a part of it is driven by the negative – a costly way to buy some insulation from the threat of crime. Add it all up, and we’re throwing a lot of money at the crime problem just to hold the murder rate constant – suggesting that something is broken.

    I agree that all this is in the context of a long process of self-domestication and that we’re much less violent than our very very distant ancestors. The politically salient point though is that on this important issue, we are doing much worse than we could be given the resources we are throwing at the problem. Both 1900 London and modern Singapore show that crime in modern countries is essentially a solved problem and the fact that large portions of our cities are no go zones after dark is something worth being surprised about, not just seen as an unavoidable constraint.

    * This very long article about policing Camden is eye-opening for the expensive and nifty hardware that’s now being used in police forces who are nevertheless barely able to police large sections of the city. A reminder that cutting-edge police technology in 1900 was the horse. (Though, looking down this rabbit hole led me to a cool Wikipedia page on the history of fingerprinting; the first criminal conviction based on fingerprinting happened in 1902, and Mark Twain wrote a sort of SF detective story about this cutting edge technology in 1893.)

    • Athrelon says:

      Whoops, that was me.

      • Douglas Knight says:

        Yeah, it’s a pity we spend so much on prisons, both blood and money, but the solution is to just stop. Canada and America had identical murder trends, up and down, despite Canada not increasing incarceration at all shows that it is just a waste. American incarceration has zero benefit.

        • B says:

          I think corporal punishment needs to be reconsidered. Prisons are years-long networking events for criminals.

          Also, the shameful way that the dregs are allowed to prey on the young, weak and not-yet-hardened in American prisons practically forces even those with a sincere wish to mend their ways into a gang, for protection.

          Prison was one of those well-meant reformist ideas that led straight into forced sodomy and criminal academies.

          A point that I like to make is that the old rule of the “straight and narrow” also serves the criminal:

          Straight’s for making society livable, but narrow makes sure that developing criminal characters get their shot before the bow before they can really mess up and hit the wall at a steep angle.

          So: 10 lashes for stealing a bike right away, not no sanction until you get into a serious criminal career, and then 10 years of being buggered and otherwise brutalized for a burglary.

          Also, I think that
          1) castrating major violent offenders to lower their aggression and chlorinate the gene pool, so to speak and
          2) executing people for multiple violent or sexual crimes, something along five strikes and you’re really, really out
          is just common sense. Of course, murderers and forcible rapists need to hang for their first offense, IMO.

          So I’m not exactly coming from a soft-on-crime stance here. Still, what’s happening to criminals at the moment is an absolute atrocity and needs to be changed, even ignoring how counterproductive it is.

          In my value system, the intelligent and self-controlled have a natural obligation of guidance and government towards their lessers, and right now they’re shamefully failing it by long pseudo-kindness and then, after all, cruel abandonment.

        • ozymandias says:

          Rapists hanging for their first offense is a really really bad idea IMO. Rapes are already unlikely to be prosecuted or convicted (for good reason; a lot of rapes are he-said she-said cases); the death penalty will probably only make that worse. If we talk solely about stranger rapes, which are unlikely to be he-said she-said, we get into the issue that eyewitness evidence is really terrible, victims often can’t identify their assailant on a lineup, and confessions are often forced. The Innocence Project’s data is pretty telling here: a *huge* number of convicted rapists did not commit the crime they were accused of (this does not mean the crime didn’t happen). Admittedly we have DNA evidence for more rapes now, but there are still a lot of victims who take a shower before they call the cops.

        • Anthony says:

          The other argument against the death penalty for rape (or any other crime which doesn’t leave a person dead) is that it increases the incentive for the criminal to murder the victim. If rape gets you the same punishment as murder, why not remove the witness? It improves your chances of not being caught and not being convicted, at no additional risk. Unless the cops are much more likely to follow up on a murder case than a rape case, which wouldn’t be likely if rape were also a capital crime.

    • nydwracu says:

      Speaking of SF detective stories, remember back when the Hardy Boys series made a big deal of voiceprinting? It was at least in 1970, and possibly earlier. And now…

      In May 2013 it was announced that Barclays Wealth was to use speaker recognition to verify the identity of telephone customers within 30 seconds of normal conversation. The system used had been developed by voice specialists Nuance, the company behind Apple’s Siri technology. A verified voiceprint was to be used to identify callers to the system and the system would in the future be rolled out across the company.

      The private banking division of Barclays was the first financial services firm to deploy voice biometrics as the primary means to authenticate customers to their call centres. 93% of customer users had rated the system at “9 out of 10” for speed, ease of use and security.[9]

    • Damien says:

      Doesn’t help that lots of the “crime” is drugs, a basically artificial crime; we’re both wasting resources locking up potheads and actively encouraging violent crime by creating a black market. How much of the increase in crime in the West is due to universal Prohibition?

      • Anthony says:

        A lot of crime, but not necessarily a lot of punishment. People in jail for drug offenses are largely violent people whom the prosecutor couldn’t quite make a case for their violent act, but could make an airtight case for their drug dealing. Even in states unlike Colorado, there aren’t many people in jail just for smoking pot, or even just for using heroin, even if that’s what their conviction is for.

        On the other hand, as you mention, violent people go into drug dealing because it’s illegal; you don’t hear about liquor store owners shooting up bystanders in their turf battles.

  12. jrayhawk says:

    A repeat for Scott (I pointed this out to you in chat in June), but everyone else might be interested:

    http://scholar.google.com/scholar?q=lithium+DHA

    Lithium has some direct effects on DHA metabolism.

  13. Anissimov says:

    Chemicals that cause a 5-10x greater increase in violence and social factors have nothing to do with it? Sounds pretty implausible to me.

  14. Troy says:

    On earlier threads I expressed the following worry about the proposed lead/crime link: the usual proposed mechanism by which lead is supposed to increase crime is by lowering IQs, or at least, if this isn’t the cause of the crime, it’s at least another effect of lead ingestion. That suggests that if lead is the primary cause of historical crime increases, we should see IQ decreases at times when crime increased (e.g., the 1960s). But as far as I know that’s not what we see: the data suggests that IQs have been steadily increasing for all populations (the Flynn effect). (This doesn’t rule out, I should acknowledge, that lead is one important influence on crime. But I think it’s grounds for skepticism that it’s the primary explanation of historical changes in crime rates.)

    Are the other chemicals you mention in this post known to reduce IQ (or in the case of lithium, raise it)? If so, similar reasoning might ground skepticism about their significance.

    • Scott says:

      My understanding of the “lead causes crime” explanation is that lead also damages parts of the brain concerned with making decisions, leading to poor impulse control and bad decision-making ability. It seems a very plausible mechanism, poor impulse control causing more crime.

      I suspect you might still see the IQ/crime anti-correlation, as it seems like our candidate for most of the damage to impulse control also has the side effect of damaging IQ.

      • Thomas says:

        This actually means that the very strong correlation between crime and IQ may be entirely an artefact – smarter people are not more lawabiding because they are smarter, the group they belong to is just less poisoned on average.

    • Anonymous says:

      hmm but the crime causing population is kind of small. even when crime was at its all time highest, the criminals were still kind of rare weren’t they. you could have mean IQ rise at the same time as those with the lowest IQs, those at the greatest risk for committing crime, also rose in number. crime isn’t about the averages, it’s more like a deviancy that has to do with what’s happening at one end. the average might not tell you what’s going on there. cities are interesting places. there’s libraries, books, televisions in the homes. it’s a stimulating environment. educational opportunity and attainment is greatest. so is exposure to lead and consumption of vegetable oils. it’s also an unhealthy environment. you can envision how these things could have separate effects on the “bell curve”, not cancelling ones but different ones. so lead-poisoned teenagers can cause havoc amid rising IQ.

      • Troy says:

        you could have mean IQ rise at the same time as those with the lowest IQs, those at the greatest risk for committing crime, also rose in number.

        Yes, someone mentioned that on a previous thread. I think you’re right that this is possible, but I’m not sure how plausible it is. For a rising average to be compatible with lead (etc.) causing crime by lowering IQ, it would have to be selective enough to lower IQs of prospective criminals without noticeably bringing down the average. The easiest way to do this is by only being consumed by the former population. This is somewhat plausible for whites, but less plausible for blacks, since the latter were (by the lead theory’s own lights) more affected by lead and a smaller population to begin with.

        Another way that lead (etc.) could do this is, as you say, by having different effects on people at different points on the bell curve. This is an interesting idea, and one I wouldn’t rule out, but seems a little ad hoc right now — I’d at least like to see some studies supporting this or some plausible theoretical explanations of how this might go.

        • John Salvatier says:

          Its a great point that if lead affected crime rates via IQ, it would almost surely show up in aggregate statistics. You would also expect crime statistics to more closely track IQ in general.

          Another possibility mentioned elsewhere is that lead reduces IQ *and* impulse control or some other characteristic and affects the other trait much more strongly and that its this characteristic that affects crime.

        • Douglas Knight says:

          Yes, lead does affect personality in relevant directions, but the way Nevin argues that lead has enough of an effect to matter (and really I should highly praise him for doing this at all) is by combining the measured correlations between lead and IQ and IQ and crime. This runs into the Flynn effect and the very serious problem of comparing IQ across time. And does absolute IQ really affect crime, or just relative IQ, or something? But most of Nevin’s arguments are unimodal time series correlations, which never work.

  15. James James says:

    FYI, there’s also this article, similar to the one you mention:
    http://www.bmj.com/content/325/7365/615.2
    Dobson, Roger: “Medical advances mask epidemic of violence by cutting murder rate”
    BMJ 2002;325:615.2

  16. Damien says:

    “Prison was one of those well-meant reformist ideas that led straight into forced sodomy and criminal academies.”

    Well, depends on the prisons. Norway seems rather better and more humane about it than the US. Cells that look like one-person dorm rooms, rehabilitation prison villages near release time… Of course, easier to have better prisons when you have fewer prisoners. I bet they eat lots of fish, too.

    • B says:

      Scandinavians are rather orderly and homogenous in the first place. Each time I was in Sweden, I found people there so conforming to each other (and all the formal & informal rules) that they seemed almost boring. NB, I’m from a [European] place generally regarded as punctual, staid, hard-working and orderly. Oh, and we have Spa prisons too.

      Norwegians are supposed to be similar, never been there. Treating criminals well is cheap if there are few and, more importantly, there’s little inclination towards disorderliness in the rest of the population.

      I don’t think that would work with US demographics. I don’t just mean the 800 poun… on second thought, let’s not use that metaphor – there are a lot of, let’s say, more complicated populations in the US that are lily white, and also a lot of dregs amongst the recent imports.

  17. Tom says:

    I liked it up until you cited Japan as an example of low murder & depression. Firstly there have been massive societal reforms since they lost WWII, & also Japan is an extremely depressed & suicidal country, much like the rest of asia. I stopped reading after that slip up.

  18. Evelyn says:

    The PUFA chart appears to be from the regularly updated survey Nutrient Content of the US Food Supply. Data from 1909-2006 available in multiple reports.
    http://www.cnpp.usda.gov/USFoodSupply.htm
    “The nutrient content of the food supply is calculated by using data on the amount of food available for consumption from USDA’s Economic Research Service (ERS) and information on the nutrient composition of foods from USDA’s Agricultural Research Service (ARS). Estimates of per capita consumption for each commodity (in pounds per year) at retail level are multiplied by the amount of food energy and each of 27 nutrients and dietary components in the raw edible portion of the food. Results for each nutrient from all foods are totaled and converted to amount per capita per day.”

  19. RCF says:

    What does “endpoint crime” mean? When I googled “endpoint crime” (with quotes), this article was the top result, and the rest seem to be reposts of this article.

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