The crime rate in the United States has fallen every year, repeat, fallen every year since 1991. That goes for nearly every type of crime including murder and other violent crimes.
The crime rate today is the lowest in forty years, including murder, burglary and car theft.
An article in the latest Commentary brought this to my attention because the author (Daniel Griswold) argues that the influx of illegal Latino immigrants is the reason for lower crime. Immigrants come here to find work and escape the stultifying family authority of Latin America. They want to work hard and raise their families. I know that is true.
I buy Griswold's thesis but there is much more to this matter.
Steve Levitt and John Donohue showed conclusively that the downturn in crime began in 1991 because of legalized abortions twenty years earlier. The abortion effect must have had an impact for many years but we need to know more about other effects that kicked-in afterwards.
I'm sure illegal immigration was one of the causes for the decline in crime rates but the data on that subject is not as conclusive as the abortion data that explains the beginning of the decline.