Recent research has focused on how the ethnic and racial composition of the population influences the segregation of minority populations, as well as how minorities are treated by the criminal justice system. These “minority group-threat hypotheses” contend that criminal justice punishment is one of the ways in which minority groups are regulated by the dominant society. The current article expands on this knowledge base through an analysis of the relationships between population heterogeneity and 2 indicators of punishment -- the use of imprisonment and the abolishment of capital punishment -- in a sample of 140 nations. Death penalty data were drawn from Amnesty International records and imprisonment data were gathered from official sources. Other variables under consideration included country-level economic stress and modernization, violent crime rates, political stability, and degree of population heterogeneity. Results of ordinary least squares and logistic regression analyses indicated that population heterogeneity was positively and significantly associated with imprisonment. Conversely, more homogeneous populations were significantly more likely to abolish the death penalty. These findings remained significant after controlling for modernization, political repression, violent crime rates, and economic stress. Results of the cross-national analysis also suggest that hypotheses involving the “minority group-threat” thesis should expand definitions of minority threat beyond the typical examination of race and ethnicity to include indicators of language and religion. Tables, references, appendix