Research indicates that voter identification requirements have a substantially negative impact on the voting of all groups except for Asians. Particularly strong negative effects are seen for blacks and Hispanics: a decrease in voting by 18 percent and 22 percent respectively. Even Whites show dampened turnout associated with voter ID policies. Yet for Asians, strikingly, voter ID has the opposite effect, boosting turnout by nearly 30 percent. This is an intriguing instance in which Asian participation patterns markedly differ from that of other groups.

The authors studied national survey data in federal election years from 1996 through 2004.

The data shows that racial/ethnic disparities in socio-economic resources and rootedness in the community do not explain overall group differences in electoral participation. It contradicts the expectation from an assimilation perspective that low levels of Latino participation are partly attributable to the large share of immigrants among Latinos. In fact, net differences show higher average Latino participation than previously reported.

The authors have shown that all else equal, blacks register and vote at higher rates than Whites. Among the largely immigrant groups with lower levels of participation, Latinos register and vote at higher rates than Asians. Unexpectedly, though, they showed that these group differences are conditional on nativity, because among immigrants Latinos participate more than either whites or Asians and almost as much as blacks.

"Although there has been speculation that the high share of immigrants in the voting-eligible Latino and Asian populations could help to explain their lower political participation, the impact of nativity is not uniform across groups and does not account for the differences between groups in participation," the authors wrote. "Race, Hispanic origin and immigration status apparently combine to produce distinctive collective influences on people's understanding of the political system and their engagement in it."

State voting rules are especially important because these are amenable to change, so the authors examined a wide range of these policies. There is a consistent effect for voter ID requirements. Some states have recently introduced new identification requirements and others are considering it. The evidence here suggests that this policy will depress white, black and Latino participation in electoral politics-and the effect could be especially strong for Blacks and Latinos. On the other hand liberal absentee voting policies lead to higher voter turnout except, surprisingly, for Blacks. Finally there is some evidence that a stronger immigrant service safety net is associated with greater political participation-an effect which is particularly clear for Asians for both registration and voting-but again not for Blacks.

The authors suggest that attention now needs to be focused on the contexts of participation faced by each group, and how their participation is facilitated or discouraged by their shared conditions in the communities where they live.