Is the recent drop in violent crime due to banning lead in gasoline?

Noting that violent crime has dropped pretty much everywhere (in the world!) since the 90s, and this blog post suggests that the ban on leaded gasoline (by the EPA in the USA in the 70s and 80s, and most other countries by 2000) is perhaps the best-supported explanation.

This would undoubtedly need some more research, but if it’s shown to be so, this is a very strong piece of evidence in any argument for the usefulness of federal government action, and an example of how the free market may not be able to solve some problems by itself. Thoughts?

How do you define “pretty much everywhere (in the world!)”?

In my completely non-researched position, violent crime has dropped in the western world since the 1990s due to age demographics. The baby boomers are getting old. Old men don’t typically participate in violent crime.

I’ll admit my initial reaction to your OP was “yeah, right.”

But a bit of google later, and it appears there could be some meat on those bones. Here’s a couple of examples:

Which has really got me quite curious - so thanks for a thought provoking question!

Problem is, they didn’t (and it is pretty much impossible to) control for all other possible causes. One is left with an interesting correlation that does not demonstrate causation. Any studies out there showing that gas station attendants and toll-takers have historically been more prone to violence?

This theory carries about as much believability as the vinyl-flooring-causes-autism theory.

Hey, maybe increasing exposure to phthalates reduces societal violence. Endocrine disruption and all that…

Nobody knows for sure what caused the drop in crime rates. What this article is doing is showing that there’s something that rose and fell at the same time as crime rates rose and fell. To be exact, they say that it rose and fell at a 19-year time gap (or maybe it’s a 22-year time gap), since a baby affected by the lead fumes wouldn’t be getting into crime for 19 or 22 or whatever years. There are lots of things that rose and fell over that time period. Nobody knows which of them are truly related. I know that it’s uncomfortable to not know how some rather basic things work, but you’re going to have to get used to it. We know more about planets orbiting distant stars than we do about the crime rates here on Earth.

Though I’ll never be able to convinced the unwashed masses of it, the main driver of violence is testosterone not lead, not abortion, or parenting. Hypothetically, if we were to inject males with antibodies against the LH receptor, the crime rate for violence will be so low that the U.S would be mistaken for Singapore.

  • Honesty

Nope. Everyone knows it’s due to the rise in the number of Starbucks franchises.

Correlation = causation

Birthrates have been pretty flat since 1970. So if it was a drop in young people causing the drop in crime rates, you’d expect the latter trend to have leveled off around 1990. Instead, crime-rates didn’t even start decreasing till 1990, and have continued to do so until today.

The lead explanation is the most convincing one I’ve heard. Most other proposed explanations are too local, and miss that the drop in crime has happened throughout the industrialized world. Especially if you have, as here, a good theoretical model for why the two things are linked.

The argument isn’t based purely on causation. But in anycase, I’d say that if you have two things correlated in multiple widely separated areas is in fact, a very strong argument for causation.

(also, what the hell is going on with the x-axis in your pirate graph? I’m pretty sure that’s not how graphs work)

The baby boom started, as we all know, post WWII (let’s just call it 1950), and throttled back about 1965.

Add 20 years to those dates and we have a whole bunch of young folks starting about 1970 and ending about 1985. I think that’s pretty compelling myself.

But crime continued to go up until around the early 90s. The crime stats don’t correlate very well to the age of baby boomers- it’s off by several years.

It was the safety seal on all packages after the Tylenol poisoning. It didn’t take effect right away because only OTC medications were sealed. It was only when it got to the point where the rat poison containers were safety sealed that the crime rate dropped. This is undoubtedly the cause of the decrease in crime rate.

Male testosterone levels have been decreasing globally. This article points to several different studies reporting such things:

I know in Freakanomics they put forward the theory that legalized Abortion has reduced the number of potential criminals being born to low income single mothers (the petri dish of criminal behavior, apparently). Not sure if that’s totally legit, but I can’t help but feel it is probably a factor. Especially when put in tandem with wide spread contraceptive use.

I believe hormones do have a lot to do with human thought and behavior too, but it’s much more complex than “it’s testosterone.”

Actually, now that I think about it, the sudden drop in the crime rate started with the availability of Windows 3.0. As Windows versions continued to be released, the crime rate continued to drop. This is a much more likely explanation than changes in demographics and employment rates.

Hah! You are wrong, silly person.

Using testosterone as a gas additive totally sounds like something they would have tried as a marketing gimmick back in the 60’s.

Which is admittedly a step up from the 50s, when it would have been radium.

In the early 1990s the tail end of the baby boomers were turning what, 26, 27, 28? Of course it correlates. It correlates perfectly.

The second table in this link shows:

Homicides committed by the 18-24 age group
1976 - 22.8%
1993 - 42.8%
2005 - 26.5%