NEW YORK -- A fight erupts among acquaintances, words give way to violence and a bystander is fatally shot amid a crowd of onlookers.
For investigators, solving the crime would seem simple enough: Question witnesses, identify the gunman and make an arrest.
But in this particular case - the killing of a security guard two weeks ago outside a recording studio in Brooklyn - detectives have run into a stubborn wall of silence. Among scores of witnesses, including rap artist Busta Rhymes and a half-dozen hip-hop celebrities who were present at the filming of a video at the studio, the lack of cooperation has been stunning, the authorities say.
"We believe there were between 30 and 50 people on the sidewalk at the scene of a homicide, and no one has come forward to volunteer information," said Police Commissioner Raymond W. Kelly. "It's challenging for investigators, and I find it disturbing."
Unless detectives can persuade someone to talk - multiple requests have been rebuffed - the killing of Israel Ramirez, an unarmed security guard who worked for Busta Rhymes, will likely remain unsolved.
"It's the code of the streets: You just don't talk to the cops," said Bakari Kitwana, the author of The Hip-Hop Generation. "That mistrust has a long history among people of color, but it's really taken on a life of its own."
From the streets of South Central Los Angeles to the housing projects of South Jamaica, Queens, the notion that those who cooperate with the police are traitors to their community has gained increasing currency.
Hip-hop songs vilify those rumored to have cooperated with authorities, and the rapper Lil' Kim is celebrated for lying about her friends' involvement in a shooting, even if her act of perjury led to a year in jail.
A widely circulated underground video featuring men, guns in their waistbands, warns against talking to the police, and "Stop Snitchin'" T-shirts have become the latest fashion statement among hip-hop fans.
"Everyone is jumping on the stop-snitching bandwagon," said Minya Oh, better known as Miss Info, who has a show on hip-hop radio station Hot 97. "It's all the rage. Even if you have a conversation with police, you'll be called a snitch."
Busta Rhymes, 33, whose given name is Trevor Smith, faces a dilemma that has a particular resonance to the hip-hop world. By remaining silent, he is angering the family of Ramirez and a good number of his fans. But if he speaks to the authorities, he risks harming his image. Yet even on some urban radio talk shows and Internet chat rooms, a growing number of fans have called his silence cowardly and amoral, and in New York, a group of ministers and anti-violence advocates have called for a boycott of his music.
Then there is the real possibility that his cooperation could lead to retribution. "In the hip-hop world, there's nothing worse than being called a snitch," said Greg Watkins, co-founder of the Web site AllHipHop.com. "It can be detrimental to your career and to your health."
But some rap producers and performers say that the notion of street credibility and its companion trait, an image as an outlaw, is wildly exaggerated by many hip-hop stars and a marketing ploy designed to bolster the image and appeal of artists.
Lordikim Allah, a rapper known as Boogie Banga, laments that many artists have become hostages to their tough-guy personas, fearful that if they stray from the role, they will fall out of favor. "Busta Rhymes is not his real name; it's a character he created," Allah said. "He's advertised himself as a hard-core guy, so the assumption out there is that if you're a gangster and a street dude, you shouldn't call the cops when there's trouble."
Of course, the culture of violence in hip-hop is not entirely fabricated. Rappers travel with a posse of armed guards for a reason, and the 2002 killing of hip-hop pioneer Jam Master Jay, who was thought to be above the fray, was especially disturbing to the rap world. The killing of Ramirez, whose death investigators believe was the unintended result of a petty squabble, has struck a nerve for similar reasons.
Such seemingly pointless bloodshed has provoked considerable soul searching. Ethan Brown, who writes about hip-hop, said the industry stoked widespread anger over the police harassment of minority youths and the perceived imbalance of a criminal justice system that metes out harsh sentences to low-level drug dealers. But the problem, Brown and others say, is that hip-hop fails to differentiate between those who help the authorities prosecute drug crimes and those who seek law enforcement's hand in combating violence.
"There's a real sense that the federal system is out of whack and that people are being put away for the rest of their lives based on informants," said Brown, whose latest book, Queens Reigns Supreme, details the rise of hip-hop in Queens in the 1980s and '90s. "But I think the industry has perverted a legitimate complaint about the legal system and applied it to all kinds of crime."
Or as Oh of Hot 97 sees it, hip-hop has created a monster that no one is willing or able to control. "The concepts of snitching and justice have become open to interpretation, and the problem is that no one has a handbook on how to proceed."
Law enforcement officials say they have little patience for the quandaries faced by rap figures like Smith.
In an interview, Kelly said he would ask the Brooklyn district attorney to convene a grand jury. If that occurred, Smith could be compelled to tell what he knows or face possible charges and jail time.
"A lot of this stonewalling is posturing they do to sell records," Kelly said. "But these hip-hop artists are making a lot of money. You'd like to think that there's some sort of civil responsibility that goes along with that. But apparently there isn't."