The juvenile homicide arrest rate fell another 14% in 2012, which is 43% lower than in 1960. A new report says a decrease in lead poisoning helps explain the trend.
EJI reported earlier this year on findings that exposure to gasoline lead could provide a convincing explanation for violent crime rates in the United States over the past 50 years.
Leaded gasoline consumption rose steadily from the early 1940s through the early 1970s and then fell as unleaded gasoline began to replace leaded gas. Crime rates follow the same pattern, about 20 years later: violent crime rose dramatically in the 1960s through the 1980s and then fell steadily starting in the early 1990s.
A growing number of criminologists and scientists are exploring the data that links increased criminal activity with lead exposure. New neurological research demonstrates that lead’s effects are very damaging at far lower levels than previously thought. Childhood lead exposure at nearly any level can seriously and permanently reduce IQ. Researchers have shown that lead exposure impairs specific parts of the brain responsible for planning, judgment, and impulse control, and it impairs the communication channels between these parts of the brain.
The brain is especially at risk during the critical growth period in the first years of life, and the behavioral impacts of lead exposure among preschool-age children are most evident when the affected children reach their teens and early-20s (during another period of rapid brain growth).
As a result, juvenile arrests were the first to increase after the rise in leaded gasoline emissions, and the first to fall after the United States eliminated leaded gasoline. The phase-out of leaded gas from the mid-1970s through the mid-1980s caused large declines in preschool blood lead levels, especially in central cities where Black children were disproportionately exposed to higher urban air lead and lead-contaminated dust. The Black juvenile homicide arrest rate then fell more than 80% from 1993-2004.
The latest data shows the continuation of an accelerating decline in juvenile arrest rates since 2008, reflecting documented declines in preschool blood lead over the 1990s, which are associated with ongoing efforts to reduce lead paint hazards in older housing.
In 2012, juvenile murder and rape arrest rates were 43% and 20% lower than in 1960, respectively. The 2012 data show that juvenile arrests for property crime, robbery, and aggravated assault fell more than 10% from 2011 to 2012, and juvenile murder arrests fell by 14%.