Acceptance of killing and homicide rates in nineteen nations.

BACKGROUND International variation in homicide rates may be attributable to cultural differences in acceptance of moral justifications for killing. The aim of this study is to investigate the relationships between measures of attitudes towards the justification of killing and homicide rates in diverse international populations. METHODS Four studies assessed variations in acceptance of killing among adults and young people in nineteen nations and four areas in the USA. Study 1 (1996-1997) assessed adult attitudes in Brazil, Chile, Costa Rica, Spain, and Venezuela with personal interviews in major cities. Study 2 (1999-2001) assessed attitudes among high school students in Denmark, Finland, Malta, Mexico, Netherlands, Slovenia, Sweden, Taiwan, and the UK with paper surveys administered in classrooms. Study 3 (2001) used telephone interviews to measure the equivalent attitudes among the US samples nationally and from regions in Texas. Study 4 (2002-2003) used paper surveys in classrooms to measure attitudes among high school students in Armenia, Belarus, Georgia, and the Russian Federation. RESULTS The acceptance of killing varied significantly among genders and national/regional groups. The mean attitude scores in the four studies combined were significantly correlated with national/regional homicide rates and the amount of variance explained was similar to that for social inequality (GINI). Together the attitude scores and GINI explained 65% of the variance in homicide rates. CONCLUSION This study provides evidence that variations in attitudes toward the justification of killing may be related to international differences in homicide rates.