His brother had been dead just over a year. Now the police had shot at him, too.

When Na’im arrived on Rikers Island, he was 16 years old, just over 5-foot-4. He got in fights, racked up infractions, and wound up in solitary confinement. In a cell near him was a Stack Paper friend. If they laid on the floor, their voices carried under the cell doors. They tried to make sense of jail by telling each other they were becoming men.

Eventually his family was able to pay his bail. Soon after, he was arrested again for possession of another gun and sentenced to five and a half years in prison.

Na’im came home from prison in August 2013. He was 21, and nearly five inches taller. He got a job as a janitor. He attended church with his father, and spoke about getting into construction. He cut off his braids. He had a new girlfriend.

But Na’im was having difficulty staying out of trouble. His name popped up during an investigation into a crew that sold heroin, crack, and guns along Gates Avenue.

Detectives had pieced together that one of their targets — a suspected heroin dealer — owed Na’im money and was debating whether to pay Na’im or shoot him, according to a police official familiar with the case. Police procedure required that detectives notify Na’im of the danger.

So in June 2014, detectives knocked on Na’im’s door, according to law enforcement documents and interviews with Na’im’s relatives. Na’im stepped into the hallway rather than let the police inside. The detectives kept their warning vague.

“I have an idea who it is,” Na’im said, not sounding surprised. Then he ended the conversation.

On the night of Aug. 30, 2014, Na’im was hanging with friends from Stack Paper, the rap collective. They had finished shooting a music video earlier. Sometime after 2 a.m., Na’im headed home, three blocks away.