Do you mean crime rate or gun deaths, as I am assuming this is about gun ownership? There are a number of factors influencing both areas, including societal attitudes, social programs, and standard of living. Crime, and particularly murder is affected by many factors. To list just a few - What fraction of the population lives in ghetto-like conditions? How much social disparity is there? Does the country have a drug problem? The list could be much longer, but you probably get the idea.