What caused the decline in American crime?

[Elok]

Violent crime in America dropped precipitously during my lifetime, starting around 1991 and continuing through the first decade of the oughts. It has since more or less leveled out and remained constant. This, while obviously welcome, is also quite baffling, since nobody really knows why it happened. Various theories have been proposed, but there are problems with all of them.

Legalized abortion? Maybe some impact, but women had abortions before Roe and the timing doesn't line up like you'd expect.
Our enormous incarceration rate? Statistical analysis suggests it's actually counterproductive.
Young males dropping as a percentage of the population? Didn't actually happen, despite the boomers ageing.
Crack going out of style? Should have dropped the crime rate more sharply, if that were all. And now we have meth and opiates instead.
The economy improving? But crime didn't go back up after 2008.

It's gotten to where unleaded gasoline is one of the more promising candidates. This is especially puzzling to me since the "unemployed and not looking for work" section of the population has gone up sharply in the past decade. Depressed young men with nothing to do are basically the most likely people to turn to crime. What do you folks think might have caused this?

[giblets]

One theory I've heard is reduced lead pollution from the 1970s onward because of the elimination of leaded gasoline

http://www.motherjones.com/environme...hildren-health

http://rationalwiki.org/wiki/Lead-crime_hypothesis

edit: oh, I didn't finish reading your post, you've already heard of it

[Egbert]

Violent crime has also been declining in Australia during the past couple of decades.

Nobody knows why for sure.

The best answer so far seems to be:

[Elok]

Well, what else happened around 1990? Did the USSR used to put crime-causing chemicals in our water?

[Egbert]

I can not think of anything particularly unusual that happened in either USA or Australia around 1990. Yet the rates of violent crime fell in both countries.



I fear you have asked a question that can not be answered.

[The Mad Monk]

When did the USSR break up?

[Lorizael]

https://en.wikipedia.org/wiki/High_Frequency_Active_Auroral_Research_Program

The HAARP program began in 1990.

...

The HAARP project directs a 3.6 MW signal, in the 2.8–10 MHz region of the HF (high-frequency) band, into the ionosphere.

...

HAARP is the subject of numerous conspiracy theories. Various individuals have speculated about hidden motives and capabilities of the project. For example, Rosalie Bertell warned in 1996 about the deployment of HAARP as a military weapon.^[31]Michel Chossudovsky stated in a book published by the Committee on Monetary and Economic Reform that "recent scientific evidence suggests that HAARP is fully operational and has the capability of triggering floods, droughts, hurricanes and earthquakes."^[32] Over time, HAARP has been blamed for triggering catastrophes such as floods, droughts, hurricanes, thunderstorms, earthquakes in Iran, Pakistan, Haiti, Turkey, Greece and the Philippines, major power outages, the downing of TWA Flight 800, Gulf War syndrome, and chronic fatigue syndrome.^[6][33][34]

I'm just saying.

[Aeson]

I would add the Internet. Imagine what would happen if everyone posting YouTube comments was released into the wild. Chaos.

Lead is appears to explain a lot of it.

[Proteus_MST]

I would add the Internet. Imagine what would happen if everyone posting YouTube comments was released into the wild. Chaos.

...

Very likely had something to do with it, although the Internet during the 90s still was a geeks playground, which only at the beginning of the 90s became accepted in the wider (non geek) public.

May be also socioeconomical changes (higher invididual wealth) and societal changes (like decline in racism, less nationalism after the breakup of the USSR, decline in religiosity)

[BeBMan]

It's either chemtrails or has to do with the equally mysterious disappearance of bees. Other than that I dunno

[kentonio]

It tallies pretty neatly with the crack epidemic of the 80/90's to be fair.

[Sir Og]

My vote is for videogames.

[The Mad Monk]

Your vote is always for videogames.

[rah]

I've heard claims that it's not really the decline we should be looking at but the increase that started in the 60 when all the Vietnam vets returned hone from the war. It was a brutal war that claimed a generation. They were not welcomed as heros when they came home and many took offense to that. PSD was not really understood back then.
Finally by the 90's that generation got older and lost a lot of the ability to be as active and the levels are now returning to where they were prior.

Probably just another garbage theory but maybe probable.

[kentonio]

I've heard claims that it's not really the decline we should be looking at but the increase that started in the 60 when all the Vietnam vets returned hone from the war. It was a brutal war that claimed a generation. They were not welcomed as heros when they came home and many took offense to that. PSD was not really understood back then.
Finally by the 90's that generation got older and lost a lot of the ability to be as active and the levels are now returning to where they were prior.

Probably just another garbage theory but maybe probable.

Seems like a plausible start to a chain effect. Lots of disaffected angry people with various levels of PTSD come home, heavy drug culture sets in and begins to influence the behaviour of not just that generation but the next who grew up with angry, troubled parents and then decades later the violence starts to drop off as the country starts to actually deal with the problems that caused it. Seems as likely as anything else I've heard.