The warning came from D.C. Taxicab Commissioner Sandra Seegars. In the aftermath of yet another killing of a taxi driver in the District on Tuesday, she urged cabbies to pass up "dangerous looking" people and to stay out of "dangerous neighborhoods."

"If a police officer sees a cabbie going into an area that's not too inviting, they should follow him for his own safety," Seegars said during a recent television interview.

"Dangerous." "Dangerous looking." "Not too inviting."

What exactly did that mean?

"When I say dangerous looking," Seegars, who is black, explained to me, "I mean a young black guy, okay, with his hat on backwards, shirttail hanging down longer than his coat, baggy pants down below his underwear and unlaced tennis shoes. That's the look."

And a dangerous neighborhood?

"If they were going to Capitol Hill, I'd take them," she said. "But if it's out there by 59th and East Capitol Streets, I wouldn't."

What Seegars was talking about has been described benignly as "rational discrimination." It constitutes prejudiced action based on so-called empirical reasoning, and its practice has long been an unspoken fact of life among area shop owners and cabdrivers alike.

But this is the first time in recent memory that a D.C. public official has come out and endorsed such controversial behavior. And yet, her remarks--aimed so obviously at low-income blacks--hardly drew a stir.

Perhaps it is a sign of the widening economic gap within black America, which is larger than the gap between blacks and whites as a whole, that the black middle class has reacted with the same acquiescence that you'd expect from your average white person.

"If something tells me, 'Don't pick this guy up,' I'm not going to do it," said Thomas Redmond, a black driver with the Madison Cab Association. "You have to trust your instincts. I could be passing up Jesus Christ, but if my gut says don't stop, I don't stop."

By all accounts, his fellow driver, Beautfort Garrett, didn't bother with such uncertainties. Garrett prided himself on complying with the law and just picking up anybody who wanted a ride.

"He was friendly and well-spoken," said Melvin Sydnor, co-owner of Madison Cab. John Smith, the other owner, added, "He was one of those cabbies who liked to talk and joke with his customers."

"If he saw your hand up," Redmond recalled, "he'd pick you up."

One of those riders apparently shot Garrett in the head and robbed him on Anacostia Drive and Ames Street SE on Wednesday morning. In November, one driver was stabbed to death and another was stabbed and robbed. And on Thursday, a cabdriver waiting at a red light was struck by a bullet in the 3500 block of Georgia Avenue NW.

Redmond and other cabdrivers say they believe that illegal drugs remain the driving force behind attacks on cabdrivers.

"They'll stick you up in a minute for that $40 hit," Redmond said.

In the midst of a rash of attacks on District cabdrivers in 1989, as the crack cocaine epidemic moved into high gear, an older black cabdriver explained his willingness to bypass black males by telling The Washington Post, "I'd rather be fined than have my wife a widow."

By 1993, a survey conducted for the Lawyers Committee for Civil Rights found one-third of the taxi drivers in the District routinely refused to stop for black customers.

At the time, black scholars Henry Louis Gates Jr. and Cornel West were among those who reportedly found it difficult to hail cabs because of their race. Chicago Tribune columnist Clarence Page would write that in order to hail a cab he had to "dress well," so as not to be confused with a welfare recipient.

During an interview with cabdrivers at the Madison Cab Association in Cheverly, I was dressed in sweat pants and a pullover sweater. One driver told me that "a black man dressed in a three-piece suit will always get a ride while someone dressed like you probably won't."

Cabbies found to discriminate on the basis of race can be fined up to $500 and lose their license.

Several years ago, the U.S. Labor Department found that driving a cab was the riskiest job in America, with an occupational homicide rate higher than police officers. At the same time, District officials began to crack down on drivers who discriminated against blacks.

"It's a tricky situation," Redmond said. "On one hand, you're talking about my losing my license, which is my livelihood; on the other hand, you're talking about losing my life."

As Seegars sees it, a small group of uncouth blacks is giving all blacks a bad name, and either that group cleans up its act or else they'll be singled out for punishment while the rest of us will just have to tolerate a certain amount of inadvertent discrimination.

"It's the old saying, 'One bad apple spoils the bunch,' " Seegars said. "You have to do something about the bad apples."

But judging prospective fares on a sidewalk from a moving cab is not a simple matter.

"I've been robbed at gunpoint three times so far," Redmond said. He listed the locations: 1st and K streets NW, the 800 block of Madison Street NW, and 10th and G streets NE.

Not one of them in a so-called "bad neighborhood."