Study: Stand Your Ground Laws Increase Homicides

[DanTex]

9. Actually, more guns do equal more crime.

More homicide, to be precise...

This paper examines the relationship between gun ownership and
crime. Previous research has suffered from a lack of reliable data on
gun ownership. I exploit a unique data set to reliably estimate annual
rates of gun ownership at both the state and the county levels during
the past two decades. My findings demonstrate that changes in gun
ownership are significantly positively related to changes in the homicide rate, with this relationship driven almost entirely by an impact
of gun ownership on murders in which a gun is used. The effect of
gun ownership on all other crime categories is much less marked.
Recent reductions in the fraction of households owning a gun can
explain one-third of the differential decline in gun homicides relative
to nongun homicides since 1993.

http://www.kellogg.northwestern.edu/faculty/dranove/htm/dranove/coursepages/Mgmt%20469/guns.pdf

This paper provides new estimates of the effect of household gun prevalence on homicide rates,
and infers the marginal external cost of handgun ownership. The estimates utilize a superior proxy
for gun prevalence, the percentage of suicides committed with a gun, which we validate. Using
county- and state-level panels for 20 years, we estimate the elasticity of homicide with respect to gun
prevalence as between +0.1 and +0.3. All of the effect of gun prevalence is on gun homicide rates.
Under certain reasonable assumptions, the average annual marginal social cost of household gun
ownership is in the range $100 to $1800.

http://home.uchicago.edu/~ludwigj/papers/JPubE_guns_2006FINAL.pdf