THE punch that ended Rob Viscome's life has now been called a crime.
Ten days ago, Patrick Rukaj, 16, was charged with misdemeanor assault in the death of the 17-year-old Westchester football player whom he tangled with at an impromptu and parentless beer party in April. Mr. Rukaj's punch leveled Mr. Viscome. His head hit a stone patio, and he died seven days later.
But a thornier question is what happened after the punch, with more than a dozen teenagers suddenly caught between the unimaginable prospect of a friend dying and the utterly imaginable adolescent anxiety of being caught partying.
''I was screaming, 'Call 911, call 911.' They were, 'No, no, no, no,' '' Mr. Rukaj told the police, according to an interview transcript.
Asked why, he said, ''They don't want any of the cops coming there and seeing all of the alcohol.''
Police witness statements made available to The New York Times show panicked teenagers trying to revive their friend for up to 20 minutes instead of calling 911, and then, some witnesses say, dropping him on his head while carrying him to a car.
Mr. Rukaj and others screamed for someone to call for help. A girl told the police she asked for a cellphone to call 911 but, ''Nobody moved.'' When they decided to drive Mr. Viscome to the hospital, she said, ''I just remember people saying, 'Not me, not me.' '' Another girl said someone asked that his car not be used because he ''did not want it to get dirty,'' according to a police report.
One friend used her fingers to keep an unconscious Mr. Viscome from biting his tongue. Others propped him up, threw water on his face.
Before the ride to the hospital in a girl's BMW, one witness told the police, someone said, ''Just say it happened at a park.''
It actually happened in a wealthy section of Harrison after the high school canceled afternoon classes because of a power failure. Teenagers converged on Beth Porzio's house, with her parents out of town.
The dispute started small, witnesses said, escalating when Mr. Viscome, who had been drinking heavily, taunted Mr. Rukaj about his father, a millionaire lottery winner now in prison for murder. ''Don't ever talk about my dad,'' a witness said Mr. Rukaj warned before landing the punch.
Ms. Porzio was not present when the fight occurred and when her brother, John, a student at a local private high school, was called home, he was angry, witnesses said. Mike Ramos told investigators that Mr. Porzio said, ''You gotta get him out of here; this didn't happen here.''
Mr. Porzio told detectives he insisted on getting Mr. Viscome to the hospital. He said the park explanation came up because ''everyone was kind of watching their own.''
TEENAGERS deposited their empty bottles in a distant trash bin and initially gave the police the park story. At the Porzio house, officers found about 10 teenagers who at first offered no information, Capt. Anthony Marraccini said.
The teenagers ''lied and deceived us and didn't say anything,'' Captain Marraccini said. ''It's really a sad commentary.''
And an unsatisfying ending.
Obstruction charges against six teenagers were dropped. Lying to the police is not illegal, nor is failing to flip open your cellphone and call 911 for an unconscious friend.
''I find their actions reprehensible,'' said the Harrison police chief, David R. Hall. ''Unfortunately, there's not a whole hell of a lot we can do criminally.''
Jeanine F. Pirro, the Westchester district attorney and a neighbor of the Porzios, who had contributed to her campaign, was publicly lambasted when a grand jury returned no indictment in July. She went to another grand jury, filed the misdemeanor charge against Mr. Rukaj and called for laws against obstructing criminal investigations of a death and lying to the police.
Of the teenagers who were not charged, she said, ''If they have a conscience, they're going to suffer for this.''
The search for accountability falls to the Viscomes, whose lawyer, Jonathan Lovett, promises a lawsuit against several teenagers.
One teenager who was at the party gave a benign explanation. ''People were unaware of how grave the situation was, and that's why no one realized that it was dangerous, real dangerous,'' he told the police.
But another, Alan Strozza, told the police that when he arrived, John Porzio, grasping the unfolding tragedy, said, ''Your boy is gonna die.''
After Mr. Viscome was taken to the hospital, other teenagers followed, deeply shaken. First, a couple of them wolfed down fast food they had on hand, and stopped to dump the telltale trash.