The most important legal development regarding hate crimes is the U.S. Supreme Court's unanimous ruling in Wisconsin v. Mitchell (1993), which upholds the constitutionality of bias-crime penalty-enhancement laws. Current social research on bias violence, although limited, presents a disturbing portrait of the fragile and sometimes violent nature of intergroup relations in the United States. Compared to crimes generally, bias crimes are more likely to involve excessive violence, random attacks, multiple offenders, serial attacks, intentional interference with exercise of a specific civil right, heightened trauma to victims, and increased risk of intergroup violence. Existing statistics show an increase in bias crimes over the last several years, but these increases may be largely due to the heightened awareness of victims and police and more precise recordkeeping. Still, the increase across the board shows that a serious problem exists. Several factors will increase the likelihood of continued bias violence over the next decade. These factors are dramatic demographic changes; the shift to a service economy that will involve immigrants, minorities, and women; the prevalence of negative stereotypes in American culture; the attitudes and atmosphere of intolerance; the proliferation of violence; youth and schools; and international disputes and terrorism. Other factors are the persistence of hate groups, minorities fighting minorities, and the continued skepticism of governmental authority and regression to an in-group. 94 notes