Re: GUNS: University of Chicago study

Brian D Williams (
Mon, 7 Jul 1997 08:28:13 -0700 (PDT)



Using cross-sectional time-series data for U.S. counties
from 1977 to 1992, we find that allowing citizens to carry
concealed weapons deters violent crimes and it appears to
produce no increase in accidental deaths. If those states
which did not have right-to-carry concealed gun provisions
had adopted them in 1992, approximately 1,570 murders; 4,177
rapes; and over 60,000 aggravate assaults would have been
avoided yearly. On the other hand, consistent with the
notion of criminals responding to incentives, we find
criminals substituting into property crimes involving
stealth and where the probabilities of contact between the
criminal and the victim are minimal. The largest population
counties where the deterrence effect on violent crimes is
greatest are where the substitution effect into property
crimes is highest. Concealed handguns also have their
greatest deterrent effect in the highest crime counties.
Higher arrest and conviction rates consistently and
dramatically reduce the crime rate. Consistent with other
recent work (Lott, 1992b), the results imply that increasing
the arrest rate, independent of the probability of eventual
conviction, imposes a significant penalty on criminals. The
estimated annual gain from allowing concealed handguns is at
least $6.214 billion.