Oakland, California, across the Bay from San Francisco, has long led America toward its racially diverse future, with at least four major ethnic groups. From the Oakland Tribune:

Report: African-Americans compose 28 percent of Oakland's population, 62 percent of police stops 

By Matthew Artz 

Oakland Tribune

... The report did not include data on the percentage of crime suspects described to police as African-Americans. Separate Oakland police records show that from 2007 through 2011, about 70 percent of those arrested were African-American. Last year, police said 90 percent of robbery suspects were described as African-American. 

Sam Walker, an emeritus professor in the criminal justice department at the University of Nebraska Omaha, who has reviewed stop-and-frisk police tactics in New York City, said Oakland police stops were far more likely to result in arrests or the confiscation of a weapon. 

In New York City, there was little evidence of criminal activity to justify the police stops, he said. "In Oakland, it's a very different picture." 

Franklin Zimring, a criminologist and professor at Berkeley Law School, pointed to the data showing that 14 percent of police stops involving African-Americans resulted in felony arrests, compared to 7 percent for Latinos, 6 percent of Asians and 5 percent of whites. 

"In terms of conventional mathematics, that is the opposite of racial profiling," he said. 

While traffic issues were the most common reason people were stopped by police, African-Americans were far more likely to be stopped on the basis of "probable cause" or "reasonable suspicion" than members of other racial groups. 

African-Americans stopped by police were searched 42 percent of the time, compared to 27 percent for Latinos and 17 percent for whites and Asians. Yet, those searches resulted in the recovery of contraband 27 percent of the time for African-Americans and Latinos, 28 percent of the time for whites and 25 percent of the time for Asians.

The question I have is why does Oakland have a distinctive "flavor," combining black criminality with political radicalism? I see it all the time in the news: if there's going to be a black political riot over some bit of news somewhere in the country, it's most likely to be in Oakland (with L.A. the second most likely).

This combination goes back at least to the Black Panthers in the 1960s. But maybe this combination of a culture of political radicalism and masculinity goes back even further before blacks arrived in large numbers for WWII military factory work: after all, the entertainment district in Oakland is named Jack London Square. And then there's the phenomenon of Raider Nation, the Oakland Raiders' obtrusively non-genteel fan base.

One vague theory I have is that the weather is so nice in Oakland (much better than in foggy San Francisco) that bad behavior is a long term strategy to prevent complete gentrification.