Two distinct groups of mourners filed past Jay Randall's open casket. There were the clean-cut, polite ones from the first half of his life, his happy childhood in Reston when he was sweet-natured and popular enough to be elected student body president at Hunters Woods Elementary School.

Along the back wall of the church on Thursday stood the others--a row of grim-faced young men wearing gold chains, sweat shirts and wide-legged jeans who knew Randall as "Baby Jay" because he looked even younger than his 16 years. Friends said the high school dropout was living the thug life, dealing crack cocaine, flashing wads of cash and running with an older crowd.

"Everything he did," said one friend, Kamau Brooks, "he wanted it fast."

Randall's parents--his father is a lawyer, his mother a health care representative--struggled mightily to reel their only son back from the streets. In recent months, they discerned some progress. He had talked about his plans to return to school.

But that was just hours before they got the news: Their son was fatally shot June 12 outside a high school graduation party at a Herndon swim club, apparently in an exchange of gunfire with the man who hosted the celebration for his daughter.

The tragic end left James and Peggy Randall wondering again how their bright, promising son could have turned so sharply from the nurturing suburban life they offered.

His parents and his older sister, Christin, now a college senior, created a stable home for Jay Randall on Steeplechase Drive. Teachers and friends who knew him in the early years said there was no reason to expect the boy to grow into anything other than a mature, likable young man.

He played sports rabidly, including swimming, football, basketball, baseball and soccer, and developed an outgoing personality. "He was delightful," recalled Rebecca Williams, his fourth-grade teacher. "He really stood out as a happy kid, funny, friendly." Doyle Brown, a student with Randall at Hunters Woods, said, "He was easy to get along with because he'd always do whatever you wanted to do."

In addition to running successfully for president of student government in the sixth grade, Randall frequently offered to speak or perform at school assemblies. "He was not shy," Peggy Randall said. "His teachers told me as early as second grade, 'Get him into drama.' "

Things changed when the boy entered Langston Hughes Middle School. "The anti-educational values really seemed to surface in him around that time," James Randall said.

The school had discipline problems before Jay Randall arrived, and it was cracking down. His smart mouth in the classroom brought him trouble, his parents said. He developed a resentment toward authority, which his parents ascribed to teenage rebelliousness.

He also grew heavily devoted to Tupac Shakur, the rapper who became a film star, a convicted sex offender and finally a martyr after he was gunned down in Las Vegas in 1996. "Tupac was his hero," James Randall said of the rapper, who had "Thug Life" tattooed across his chest. The father worried about the profanity and misogyny in rap lyrics but felt he couldn't stop his son from listening to music.

Jay Randall finished eighth grade, but things were worse at South Lakes High School, where he skipped classes so often he received F's across the board. Teachers and administrators met with the Randalls and said the parents were willing to do whatever was necessary. After one semester in which Jay did not earn a single credit, his parents pulled him out of South Lakes, and Peggy Randall began driving him to alternative high schools. The boy still skipped classes, or back-talked in the ones he attended.

Numerous friends of Jay Randall said he began selling drugs around age 14. "He wanted to be a thug," said Raschad Winston. "I knew him when he was a goody-goody. He started getting around the wrong people."

When his increasingly desperate parents found marijuana on their son, they decided to call the police in hopes the shock would set him straight. "We thought we could use the system to get help," Peggy Randall said.

The youth was placed on probation. But when he missed his court-imposed curfew and faced 30 days in the lockup, he vanished for more than a year. He was 15.

Peggy Randall often couldn't sleep, afraid of what her son might be doing. She started attending parent support groups and counseling with her minister. "I prayed that he would be protected," she said. "It got scary when time would go by and we wouldn't hear from him."

Jay Randall hid mostly with different women, his sister later learned. Friends said women were attracted by his ready supply of cash, but also by a certain charm. "He was a ladies' man," Winston said. "It seemed like they almost mothered him," Peggy Randall said. Dozens of young women packed the sanctuary at his funeral.

Earlier this year, Jay Randall was picked up by police, and he served his time. His parents saw a ray of hope when, while in detention, he earned a high school equivalency degree. That was highly unusual for a 16-year-old, especially one with as little high school experience as Randall. He came home to Reston in March and lived with his parents again.

"In the last four months, he'd been very accommodating," his father said. He turned down the music when asked. The arguments with his parents dwindled. His sister helped him to get a driving learner's permit and to take classes for a lifeguard's job. If he was running with his old crew, his family didn't know it.

Shauntai Bennett, who lives with her parents and brother on a quiet cul-de-sac in Sterling, apparently knew nothing of Jay Randall. At Park View High School, where she was a senior, students described her as quiet, with many friends outside the school. "She's really nice, but she wasn't really talkative," said Julie Eppard, a fellow senior.

Her father, Eddie Bennett, agreed to throw a graduation party the night of Saturday. June 12. He declined to be interviewed for this article, but his attorney, John Partridge, described Bennett as an entrepreneur who formerly owned Ed's A-1 Refuse Service and now works in the auto business and dabbles in baseball card sales.

"They are proud of their daughter and wanted to have something for her," Partridge said. Relatives of the Bennetts rented the Four Seasons pool and clubhouse at 1201 Herndon Parkway, invited friends and classmates, laid out snacks and set up music.

Eppard said that she didn't go to the party but that other students told her it had been relatively quiet for most of the evening.

As the evening wore on, Partridge said, crowds of youngsters began congregating around the clubhouse. Although the invited guests were largely from Sterling, word spread through the Herndon neighborhood about the party. Eddie Bennett worried about the noise and tried to disperse the crowds, Partridge said. When that didn't work, he called the police. But by the time they arrived, the disturbance had quieted.

A neighbor who was parked in the same lot, Sufian Ghannan, said that about 11 p.m., he spoke with a group of several young men--including Randall--who told him that there had been a fistfight on a slope above the parking lot, and that they were planning to return and look for the fighters. Ghannan, who knew Randall, said the youth didn't say anything. "He was quiet, and that's not normal for him," Ghannan said.

What happened next remains unclear. According to Partridge, Eddie Bennett and other family members were stacking chairs and cleaning up around midnight when several uninvited guests who had been asked to leave the party showed up armed.

Eddie Bennett's brother, who declined to give his name, said that one of the intruders even held a gun to his nephew's head and that he tried to pull the gunman away. "I grabbed the guy," Bennett's brother said. "I was sure I was going to be shot."

Partridge said Eddie Bennett, fearing for his safety and his family's, pulled out a gun he carries as a matter of habit because he works late hours and is concerned about security.

At least six shots were fired, police said. According to Partridge, one of the intruders opened fire first, and Bennett returned the shots. Randall was struck in the chest and died the next morning. A 21-year-old man who was with him was hit in the abdomen and survived.

Partridge said he doesn't know whether Bennett has a permit to carry a concealed weapon. Police have found no record of such a permit. Bennett was questioned by police for several hours after the shooting but was never placed in custody, according to Partridge.

Herndon police have not said whether they believe Bennett's version of events is accurate. In the absence of official information, rumors have flowed, including allegations of gang involvement and claims that Randall was shot at point-blank range. Investigators would not comment on those claims.

Bennett and his family say the shooting was a matter of self-defense, but they are so distraught that they "just want to go back and retreat and pretend it never happened," Partridge said. Any resolution must wait at least until police finish their investigation of the incident and present the results to Fairfax County Commonwealth's Attorney Robert F. Horan Jr. He will decide--probably this week--whether Bennett should be charged with murdering Randall, or whether the shooting was justified.

Whatever the outcome of the investigation, the Randalls say it won't resolve their family's question how their son wound up dead at 16.

In the past few months, Jay Randall appeared to be making an effort to escape the thug life. James and Peggy Randall said the tension at home had eased, and they were encouraged when their son said he planned to enroll this fall at Northern Virginia Community College.

"We were trying not to fight," James Randall said. "Fighting had just driven him away before."