UPDATE: Cardone Pleads Not Guilty to Murder in Sunday's Stabbing

Joshua Cardone, a 19-year-old Concord resident who police believe another man outside a Burger King in the Clayton Valley Shopping Center Sunday, pleaded not guilty to first-degree murder charges at the A.F. Bray Courthouse in Martinez on Wednesday.

Prosecutors charged Cardone with first-degree murder with an enhancement for the use of a knife, said Contra Costa County Deputy District Attorney John Cope.

After the arraignment, Cardone's attorney Michael Cardoza said, "There's a good case for self-defense here."

Cardone is expected back in court on May 10. He is in custody on $1 million bail.

According to police, Cardone was involved in a dispute with the victim, 20-year-old Concord resident Richard Gilliam, in the shopping center parking lot when Cardone stabbed Gilliam.

Police were called at about 4:20 p.m. When they arrived, they found Gilliam in the parking lot with at least one stab wound. He was taken to a hospital, where he died.

Cardone remained at the scene and witnesses identified him as the stabber, police said.

Cope said he couldn't release details about the nature of the dispute or the circumstances of the stabbing because investigators are still interviewing witnesses, many of whom knew Cardone.

He did say, however, the two men "were not strangers to one another."

Monica Kelly, who works nearby the Burger King where the stabbing took place, said she witnessed the killing.

She was on a break when she saw a couple dozen young people gathered and heard them saying things like, "We need to teach him a lesson" and "We need to show him who's boss."

Kelly said she then saw the man on the ground and a woman trying to stop the bleeding.

The defense said they will be looking into Gilliam's background when it comes to this case.

"We understand that the deceased in this case has a past that needs to be vetted," Cardoza said.

According to court records, Gilliam has one pending misdemeanor charge of possession of a deadly weapon, but no other adult criminal history in Contra Costa County.

As to the question of why Cardone remained at the scene, Cope said, "Some people who (act) in self-defense stay and some people who want to pretend they acted in self-defense stay, and that's what we have juries for."

Bay City News contributed to this article.