Why has crime, especially younger-age crime, plunged so dramatically in virtually every jurisdiction over the last 20 years regardless of its anti-crime policy or non-policy? We looked at standard explanations for the startling fact that today’s California and national youth and young adults represent the least criminal and violent generation ever reliably assessed.
None suffice. Most social and institutional conditions thought to generate more crime have not improved. Youth poverty rates remain high, families as chaotic, kids spend more time with peers than ever. The alleged grownups are acting worse, with more middle-aged drug abuse, criminal arrest, and incarceration, though the rapid increases of the 1980s and ’90s are leveling off. Young people still face diminished and defunded schools, universities, job prospects, and services.
Still, California youth, the most diverse and poorest demographic, policed and incarcerated less than any previous generation, now display the lowest levels of crime ever reliably recorded. For all the fretting about more violent and explicit pop culture available to ever-younger kids, the youngest young are becoming less criminal faster than the oldest young.
Maybe that’s our answer: Just leave them the hell alone.
We are seeing conventional crime theory fall apart. If history is any teacher, it will take conventional authorities another half century to notice. Criminologists resemble priests, not scientists, stuck invoking the gods of demographics and broken windows llike their ancestors.
Well… could it be something as simple as cleaner environments? Could the Environmental Protection Agency be America’s top crime fighter?The one factor found so far that tracks both crime rates and trends is average blood lead levels. Economic consultant Rick Nevin has published extensively on environmental and blood lead levels in several Western countries and found that while their violent crime rates peaked and ebbed at different times, all tracked their respective trends in lead exposure.
Lead in the human body is bad stuff. It has many toxic effects, including those relevant to criminality. The body’s lead content is linearly associated with slower and faultier development of the brain’s pre-frontal cortex and executive functions, which in turn leads to diminished impulse control, executive decision-making, and behavior regulation. (This holds great irony in terms of pop-science notions of “adolescent development,” a topic for a future blog.)
Poorer urban populations have higher lead levels as a rule due to living in older housing and traffic- and industry-polluted central areas. African Americans have by far the highest amounts; Hispanics the second most; Asians and Whites, lower levels.
In the late 1970s, 88% of children ages 1 – 5 tested had blood lead levels of 10 micrograms per deciliter of blood (equal to 1⁄10,000th of a gram of lead per liter of blood) considered the level defining toxic physiological risk) or higher. Environmental measures indicate the 1970s were a peak period in terms of the maximum exposure of children to lead paint in households and lead in the atmosphere from increased postwar leaded gasoline use and driving. Back then, the average low-income child accumulated lead to twice the toxic threshold.
Lead use in paint had been dropping throughout the century before being banned in 1978, and was phased out in gasoline from 1970 to 1990. The results were astonishing. From 88% in the late 1970s, the percent of children ages 1 – 5 with blood lead levels of greater than 1 part per 10,000 fell to 9% in the late 1980s, 4% by the mid-1990s, 2% by 2000, and 0.5% in 2010.
Disparities remain. Males have consistently higher lead levels than females. African American levels remain around 5 times higher than for Whites and 2 – 3 times higher than for Latinos and Asians – but all at far lower accumulations than 40 years ago.
Remembering the perils of assuming correlation equals causation, consider now the crime trends. Children ages 1 – 5 in the 1970s, those with record levels of lead toxicity, reached their teens by the late 1980s and young adulthood by the early 1990s. This is exactly the period during which violent crime, including homicide, spiked to record levels among African, Latino, and Asian Americans under age 25 but remained steady among older ages and White youth.
High crime rates have aged as child generations of the 1960s and 1970s with higher lead exposure have moved into middle age, with 50-agers now showing the most rapid increases. If “lead exposure theory” is valid, we should see juvenile and young adult crime begin to level off at historic low rates, the 40-age crime increase should continue its recent downturn, and over-50 rates continue rising for a few more years before reversing as well.
In short, among the socioeconomic measures such as poverty, income, unemployment, education attainment, etc., lead exposure may prove the best single variable predicting crime. However, the fact that lead has toxic effects on brain functioning also calls into question punitive policies aimed at offenders whose chief crime was being raised in a time and place where concentrated poisons were allowed.