Issues demographic experts face concerning voting rights litigation are considered, using examples from Garza v County of Los Angeles (California) (1990). Errors and the age of census figures when released mean that court decisions about appropriate population bases and thresholds will continue to vary from one location to another. (SLD)

Advocates of the use of ecological regression as an indicator of ethnic voting behavior have not demonstrated its validity. The neighborhood model, which assumes that within each precinct Hispanic Americans and non-Hispanic Americans vote alike, is supported as a better way to draw conclusions about voting behavior. (SLD)

Statistical analysis of racially polarized voting prepared for the Garza v County of Los Angeles (California) (1990) voting rights case is reviewed to demonstrate that ecological regression is a flexible, robust technique that illuminates the reality of ethnic voting, and superior to the neighborhood model supported by the defendants. (SLD)

Issues surrounding a recent voting rights case in Los Angeles (California) are discussed and evaluated in this introduction to the remainder of this special issue. The most important issues are geographical compactness, political cohesiveness, and racial voting blocs. (SLD)

The use of ecological regression in voting rights cases is discussed in the context of a lawsuit against Los Angeles County (California) in 1990. Ecological regression assumes that systematic voting differences between precincts are explained by ethnic differences. An alternative neighborhood model is shown to lead to different conclusions. (SLD)

D. Freedman and others and W. Clark and P. Morrison misunderstand case law in the voting rights area and have unrealistic standards of precision that, if adopted, would make it virtually impossible for minority plaintiffs to succeed. Ecological regression, when used with care, is a reliable tool. (SLD)

How technical demographic analysis can inform and confuse judicial considerations of voting rights principles is illustrated in a review of a 1990 case brought against Los Angeles County (California). A postscripted article considers whether the court involved should rely on after-census estimates for redistricting. (SLD)