It is perhaps the most explosive racial issue in America today: White police officers shooting and killing minority residents. In New York it was African immigrant Amadou Diallo. In California it was Tyisha Miller, a black woman in a parked car.
Well, in Chicago, police recently killed two unarmed black motorists in separate incidents. But here there's a twist: Both of the officers who reportedly fired the shots are black. One is a woman.
It's a difference some observers say gives credence to the idea that police brutality isn't caused so much by the simmering racism of individual cops. Rather, the overzealous, militaristic culture of some police departments is partly to blame, too.
More than dismissing a few bad-apple cops, these experts say, the solution lies in altering the fear and ethos of machismo in the nation's police barracks.
Furthermore, the Chicago cases raise questions about whether diversity in police ranks can help dissolve mistrust between civilians and cops. Some argue that racism is hardly confined to white cops. They say racial sentiments provoke black-on-black confrontations as well.
"If you're training cops to think they're in a war - including a drug war - you're going to get atrocities like this," says Joseph McNamara, a former police chief of San Jose, Calif., who's now a research fellow at Stanford University's Hoover Institution.
And, he says, "There are too many of these cases nationally to write them off to a few misjudgments."
In the Chicago case, Robert Russ, a black Northwestern University football player, was killed, police say, when he tried to grab a gun that an African-American officer pointed inside his car after an early-morning chase.
A day earlier, computer programmer LaTanya Haggerty, a passenger in a car involved in a chase after a traffic stop, was shot when an officer mistook her cellular phone for a gun, police say.
Investigations are ongoing - as are protests, which have even attracted the Rev. Al Sharpton from New York.
Protesters say these cases aren't isolated. Last year, Chicago police shot 71 people, the highest number in a decade. So far this year they've killed eight.
The 'credibility gap'
Police Superintendent Terry Hillard admits there's a "credibility gap" between residents and police - and has vowed to fix it. He's pledged to install video cameras on police cruisers to boost accountability.
But to really fix things, Chicago police - and departments nationwide - need to eradicate the "culture of intimidation" that's so common today, says Nicholas Pastore, a former police chief of New Haven, Conn., who's now a scholar with the Washington-based Criminal Justice Policy Foundation.
This ethic of intimidation, he says, "has displaced any thought that police officers should get to know citizens on a first-name basis."
Knowing residents on the beat not only boosts their confidence in police - but it also curtails an officer's desire to pull a gun every time there's danger. It's simply harder to shoot people you know, the rationale goes. And if officers aren't used to pulling their guns, they're less likely to do so even if they don't know the suspect.
"Keep in mind," Mr. Pastore says, "that cops go to work every day wearing a bulletproof vest and a Batman belt." So it takes great effort to keep them from feeling utterly threatened by the populace.
Indeed, other cops say their work is so dangerous that they have to be highly defensive. In 1997, 65 law-enforcement officers were killed in the United States, although that annual number has dropped over the past decade.
But Pastore and other community-policing backers say several things are to blame for the militaristic culture. The biggest is the war on drugs.
Calling it a "war," they say, fosters an unhealthy us-versus-them mentality, especially with minorities, who are arrested for drug-trafficking proportionately more than whites.
Indeed, even though the police in the Chicago cases are black, race is still a major issue, with protesters charging rampant police racism.
The charges seem credible with statistics like this: Of the 115 Chicagoans killed by police between 1990 and 1998, the vast majority - 82 - were black, a rate that's much higher than the national average.
The impact of a diversified police force
Chicago's police department, like those in many cities, has attempted to mend race relations by hiring more minorities. About one-fourth of the city's police officers are now black - although about 40 percent of city residents are black.
Yet diversity not a sure-fire fix - as the Chicago cases show. Minority cops can get just as caught up in the tough culture - and in stereotypes that label blacks and other minorities as criminals.
"Many black people who join police forces suddenly turn blue," says Pastore.
But the Rev. Paul Jakes, a central figure in the Chicago protests, says now is no time to halt diversity efforts.
In fact, he says, boosting the number of minority officers is crucial to changing the police culture. Getting a critical mass of them, he says, "would put a balance in the number of people who have greater sensitivity to minorities."