How and why does violent crime vary across racial and ethnic groups? Researchers of American social problems have grappled with this question for more than a century, with most attention being paid to differences between blacks and whites. Black-white comparisons have been the norm since W. E. B. Du Bois completed his pioneering study, The Philadelphia Negro, in 1899 (Du Bois, 1899: 235–86; see also Hawkins, 1999; Bobo and Johnson, 2000). Du Bois, like others in his era, observed the impact of crime, including violence, and criminality on conditions within Philadelphia's black community and noted the necessity to incorporate an analysis of crime into his “social study” (for a fuller treatment of the Du Boisian perspective, see Bobo, 2000).

In fact, most early examinations of the relationship between race/ethnicity and crime during the early twentieth century described the effects of cultural absorption, acculturation, and social adjustment on both black migrants and European immigrants moving into urban areas such as Philadelphia (Lane, 1979; 1986; 1997). Varying levels of criminal involvement were linked to levels of acculturation and assimilation into American society, suggesting that more than a hundred years ago criminologists were fully aware of a possible race-ethnicity-crime linkage. This connection was largely conceptualized as the product of or associated with the geographical movement of large groups of people. Moreover, racial differences in crime and violence were seen primarily in terms of black versus white, while ethnic differences were described largely in terms of foreign-born versus native-born whites (Martinez and Lee, 2000a).