Updated

The final defendant in a brutal schoolyard attack that killed three college-bound friends and left a fourth seriously wounded was convicted on Friday, marking an end to a five-year odyssey for the victims' family members who made it their mission to be present for all phases of the criminal cases.

Jurors in state Superior Court convicted Gerardo Gomez on 15 of 17 counts, including murder and attempted murder.

Gomez, 20, was among six men and boys charged in the Newark schoolyard attack, which shocked the state's largest city and led to a host of anti-crime measures. Several of the defendants were avowed members of the MS-13 street gang.

Gomez had turned 15 on the day of the killings, Aug. 4, 2007, but was tried as an adult. His attorney had argued that he was a bystander at the Mount Vernon School playground, but prosecutors contended that he acted as a lookout while the victims were robbed.

Killed were Dashon Harvey, Terrance "T.J." Aeriel and Iofemi Hightower. A fourth friend was shot and slashed but survived. All were enrolled or planning to enroll at Delaware State University and knew each other from playing in marching bands.

The defendants initially robbed the four, then led three of them down a set of steps and forced them to kneel against a wall before shooting them, according to the suspects' statements and the survivor's testimony.

Like many family members of the victims, Shalga Hightower, Iofemi Hightower's mother, attended every trial in the case.

"I feel like a load has been lifted, because we had to endure so much in these five years," Hightower said outside court following Friday's verdict.

James Harvey, whose son Dashon Harvey was killed, said the victims' families had grown so close during the trials that they now spend holidays together and would be around the same Thanksgiving table this year. He said they felt the guilty verdicts in the case had been just.

"Now our healing aspect can begin, at this particular point, where we don't have to come and face these criminals in court, day by day, and sit and listen to the events of that night," he said. "This is the end of the road for the criminal aspect, and the healing process begins."

Besides Gomez, three of the other defendants were convicted at trial and are serving multiple life sentences, and two others pleaded guilty, one to reduced charges in exchange for his testimony.

Sentencing for Gomez is tentatively scheduled for Jan. 8. Prosecutors say they plan to ask for multiple life sentences.

First Assistant Prosecutor Thomas McTigue and Assistant Prosecutor Romesh Sukhdeo said the cases were among the most upsetting they had worked during their long careers with the Essex County prosecutor's office.

"It's just an amazing waste of life," McTigue said. "These were truly innocent victims. These were good kids from Newark. These were band kids, and their lives were snuffed out for no reason."

The outcry following the killings fast-tracked numerous anti-crime measures in Newark including surveillance cameras and gunshot detection systems.