Background. It is unknown whether keeping a firearm in the home confer
s protection against crime or, instead, increases the risk of violent
crime in the home. To study risk factors for homicide in the home, we
identified homicides occurring in the homes of victims in three metrop
olitan counties. Methods. After each homicide, we obtained data from t
he police or medical examiner and interviewed a proxy for the victim.
The proxies' answers were compared with those of control subjects who
were matched to the victims according to neighborhood, sex, race, and
age range. Crude and adjusted odds ratios were calculated with matched
-pairs methods. Results. During the study period, 1860 homicides occur
red in the three counties, 444 of them (23.9 percent) in the home of t
he victim. After excluding 24 cases for various reasons, we interviewe
d proxy respondents for 93 percent of the victims. Controls were ident
ified for 99 percent of these, yielding 388 matched pairs. As compared
with the controls, the victims more often lived alone or rented their
residence. Also, case households more commonly contained an illicit-d
rug user, a person with prior arrests, or someone who had been hit or
hurt in a fight in the home. After controlling for these characteristi
cs, we found that keeping a gun in the home was strongly and independe
ntly associated with an increased risk of homicide (adjusted odds rati
o, 2.7; 95 percent confidence interval, 1.6 to 4.4). Virtually all of
this risk involved homicide by a family member or intimate acquaintanc
e. Conclusions. The use of illicit drugs and a history of physical fig
hts in the home are important risk factors for homicide in the home. R
ather than confer protection, guns kept in the home are associated wit
h an increase in the risk of homicide by a family member or intimate a
cquaintance.