Forrest, 38, was gunned down July 25, 2009 after being robbed at gunpoint by DeMario Ware, authorities said.
According to official accounts of the crime, Ware stuck up Forrest, stealing his gold championship ring and a diamond Rolex watch, as the former boxer was putting air in his tire at a southwest Atlanta gas station.
Forrest chased Ware but lost him when the man ran into an apartment complex on McDaniel Street and hid.
Forrest then encountered an alleged accomplice of Ware's, Charmon Sinkfield, who is accused of shooting the boxer seven times, including five times in the back. Crews drove the getaway car as all three men fled, authorities said.
Ware was convicted of felony murder and armed robbery in August 2011. He was sentenced to life in prison without the possibility of parole.
The state is seeking the death penalty against Sinkfield, whose case has not yet gone to trial.
During closing arguments Friday in Crews' case, Assistant District Attorney Peter Johnson pointed to Georgia's party-to-a-crime laws in connecting the defendant to Forrest's killing. He said all of the suspects' actions were planned and that they conspired to hide the murder weapon and split the proceeds of the robbery.
"Jquante Crews is just as responsible as DeMario Ware and Charman Sinkfield,” he said.
Defense attorney Josh Moore said there was little proof that Crews was intentionally involved in a scheme.
“It’s not a plot and it’s not a plan,” Moore said. "This is street violence. It was a stick-up [by Ware].”
He said Crews was trying to help a friend who was in trouble.
“Vernon Forrest’s decision to run after DeMario Ware transformed this situation in a fundamental way,” Moore said. “To a point where a person who picked a [friend] up from a place where they were hiding is responsible for murder from a point where a person is trying to help and prevent any more violence from happening.”