And so the very involvement of the Office of the Special Narcotics Prosecutor in the case was unusual. The SNP does have a Narcotics Gang Unit, established in 2002 and presided over for many years by Farinha and Susan Lanzatella, the other assistant district attorney assigned to the Shmurda case. The two Gang Unit co-chiefs are "very hands-on" and tend to handle the investigation, prosecution, and trial of their cases from start to finish, according to a person familiar with the SNP's inner workings. In recent years, the cases brought by the SNP have targeted sophisticated drug operations with millions of dollars in revenue and kilos of inventory.*

At a court hearing in January, Farinha said, "This case is not about [Pollard's] fame, or his race, or his rap lyrics, or that aspect of his life." But of course, in anything but the most literal legal sense, almost the exact opposite is true. It is about all those things in fevered combination.

By most accounts, by the late fall of 2014, Pollard was anxious, ground down, short-tempered—a suddenly rich and famous 20-year-old out of his depth and faced with compounding responsibilities, not to mention the constant attentions of the N.Y.P.D. He rented an apartment in a town house in New Jersey, an apparent attempt to put some distance between himself and the Brooklyn crowd. As early as May 2014, before those first two massive shows in Miami, Pollard revealed an awareness of his predicament. On one of those recorded phone calls his friend Slice made from Rikers—the same calls that produced much of the government's evidence of criminal conspiracy—Pollard says, "All I want is positive things, bro. I ain't got time for no hood shit. I don't care about no gang shit.… I got record labels tryin' to sign me. I don't care about none of that shit but my music and money, bro."

But in the end, Wilson, Sha Money, and others say Pollard felt an unshakable loyalty to the kids he grew up with. "They were a band of brothers," Sha Money says. Now that money was flowing in, now that he was on the verge of making it out, Pollard wanted to share with the boys who'd always had his back.

But loyalty doesn't necessarily explain everything. Wilson recalls several cryptic comments Pollard made during that summer, about why he couldn't just cut out his Brooklyn friends: "It's deeper than rap." And: "It goes deeper than what you know." One source close to Pollard has a theory: The dozens of young men who showed up for that backyard meeting in July were all members of the G-Stone Crips, the very gang that prosecutors maintain is synonymous with GS9. In a sense, if you grew up on those blocks, you were a G-Stone Crip. On the other hand, GS9 was this smaller, closer-knit group of friends who were focused on hip-hop. But because they'd grown up in GSC-land, they were citizens of it—and it was a citizenship, the source suggests, that could not be renounced: "I think a lot of those kids were forced to be gangbangers. 'Forced' as in: You're a Crip, or you're against us." And if you're a GSC citizen, and you become a hip-hop star, you may be subject to a tax.

Wilson tried one last gambit to extract Pollard from New York. In early September 2014, he tasked Ball with going up to the city and persuading Pollard to come back to Miami. "They sent me there like a Navy SEAL," Ball says. "My mission was to get Bobby out."

Ball says he found Pollard holed up at the Times Square Holiday Inn, and he was not alone. "It was like he was kidnapped by Crips," Ball says. "Blue shit everywhere. And everybody was looking at me like: Who the fuck is you?" He pauses. "Don't get me wrong: It looked like that to me. I mean, that was his squad. But it was a whole bunch of new dudes. People I'd never seen." Ball recalls having to pull Pollard, who was clearly exhausted and ill and "coughing up some green shit," into the bathroom. He turned on the water faucet so they could talk without the others hearing. "I was like, 'Bro, you gotta come home.' " Pollard assured him that he would come to Florida soon. He just needed to take care of some things first.

On March 14, 2016, Rudelsia Mckenzie took the witness stand in the trial of Rashid Derissant and Alex Crandon, the two GS9 defendants accused of murder. She was tall and middle-aged and wore her hair in a jet-black pixie. On the stand, her voice quavered, for she was the mother of the murdered boy. On the evening of February 8, 2013, her son, Bryan Antoine, 19 years old, had been shot inside a bodega in East Flatbush. He was buying soda pop. She was asked to recount the events of that evening, from her perspective. They ended at the Kings County Hospital with a doctor telling her, "I'm sorry, he didn't make it." She paused, and the courtroom was silent, except for Mckenzie's muffled sobs. Then she apologized. "It's just hard to relive that day again," she said.

Repeatedly during the trial, the prosecutors and the police detectives they brought to the stand as witnesses referred to Rudelsia Mckenzie's son as a member of GS9's purported rival, "the BMW gang." But when I spoke to her a few days after her testimony, she denied this. "I don't know why they labeled him as being a BMW gang member," she said. "Bryan wasn't in that life. It's just the friends he hung around with."

Maybe this was a mother in denial about her son's affiliations; maybe her son simply kept her in the dark. Or maybe what she said was the truth. Whatever the case, trying to grasp gang dynamics in New York City is a notoriously fraught undertaking. For one thing, New York was never like Los Angeles, birthplace of the Bloods and the Crips, or Chicago, birthplace of the Vice Lords and the Gangster Disciples. Its "gangs" were always fractured, fluid, forming and dissolving and re-forming.

David Kennedy, a researcher at the John Jay College of Criminal Justice in New York and the founder of a national violence-prevention program called Operation Ceasefire, tells me, "People think gangs are organized, purposeful, have a leadership, that they use violence to promote their illegal economic interests. In most places most of the time, none of those things are right."

But there is an institution that does often treat groups of young black males in poor neighborhoods as organized crime: law enforcement. One former N.Y.C. prosecutor who's recently entered private practice describes what he calls a "newer trend" in the city's criminal-justice system, whereby groups of kids, all friends, are lumped together and charged with conspiracy based on individual crimes—drug possession, gun possession, attempted robbery, say—that some in the group have gotten busted for. Now, he says, under conspiracy law, "you put them together as a gang and they're all responsible for all their criminal activities."

The danger, of course, is the possibility of tarring someone with guilt by association, of prosecutorial overreach. "The fact is, the law in this kind of thing is a very blunt instrument," Kennedy tells me. "Even among people who are really serious law-enforcement folks, people say we're casting too wide a net."

To compound the problem, groups identified as criminal gangs by the cops often include aspiring rappers. Social media today—not just Instagram and YouTube, but dozens of local message boards dedicated to hip-hop—is filled with homemade videos that feature the performance of what law enforcement might call "gang activity." The N.Y.P.D. monitors social media just for this.

There are rap groups that spin off from gangs, gangs that morph into rap groups, and rap groups that—as a marketing ploy, to gain the coveted street cred—pose as gangs.

It is the organizing cliché of rap: the authentic street hustler who exploits his authenticity to create hit songs, find an audience, become rich and famous. The demand for street cred is intense, and the history of the genre is filled with rappers who have felt its lack. The classic case was Tupac Shakur, the sensitive boy who played violin at a prestigious Baltimore art school. Even after he'd made it big, he aggressively sought to build street cred by surrounding himself with real hustlers—until he was shot to death on the Las Vegas Strip, his pursuit of authenticity was his downfall.

Shmurda is Shakur's inverse, in a sense. During the summer of Shmurda, as he strove to launch a career in hip-hop and, behind the scenes, struggled to break away from his old crowd, Pollard worked hard in interviews to accentuate his street cred, aware that authenticity is what would sell. He bragged that he'd dealt drugs as early as the fifth grade, that East Flatbush was like "growing up in the jungle. Gotta be hard. If you ain't hard, you ain't gonna stand, you gonna fall."