TORONTO - The first person to stand trial for Jane Creba's death didn't fire the shot that killed the teen on Boxing Day 2005 but is guilty of second-degree murder nonetheless, the prosecution said during closing arguments Tuesday.

The man, known only as J.S.R. because he was under 18 at the time of the shooting, showed a callous disregard for public safety by taking part in a gun battle that sent a hail of bullets through a Yonge Street shopping crowd, Crown attorney Kerry Hughes said.

"(J.S.R.) willingly engaged in a gunfight, discharging his firearm numerous times into a busy street teeming with people," Hughes told the jury.

"J.S.R. had to know that someone other than the northbound shooter was likely to die."

The man, now 20, has pleaded not guilty to second-degree murder in Creba's death. He also faces weapons charges and six counts of aggravated assault.

Hughes told the court that the gun battle erupted following a confrontation between J.S.R.'s group, facing south on Yonge Street, and a man who fired shots northbound.

The two contentious issues, Hughes said, are the identification of J.S.R. as one of the shooters and whether he caused 15-year-old Creba's death.

J.S.R. was arrested later that day with a 9-mm Ruger pistol, but Hughes says the defence will argue that he wasn't the one who fired the weapon, rather that he took it for the shooter.

That pistol wasn't the one that fired the bullet fatal to Creba, but Hughes said everyone involved in the gun battle must bear responsibility. She likened it to street racing, saying if a bystander is killed by a street racer, both drivers are criminally responsible.

"J.S.R. was a significant contributing cause to the death of Jane Creba," she said.

The Crown alleges J.S.R.'s group was outside a Foot Locker on Yonge Street, waiting for the man who would become the northbound shooter. Aware that the group was waiting for him, Hughes said, the northbound shooter came out with a gun barely concealed in his sleeve and made some comments to J.S.R.'s group.

Instead of retreating, at least two people in the group pulled guns and in response to the threat the northbound shooter started firing, Hughes said.

J.S.R. was not the person who brought the gun downtown that day, so at some point the gun was transferred to J.S.R., Hughes said. There are no witnesses to when the transfer happened.

The defence will likely argue Wednesday that J.S.R. took the gun after it had been emptied, Hughes said, but the Crown alleges in response to the first shot from the northbound shooter, J.S.R.'s reflex was to grab the nearest gun and start firing.