JACKSONVILLE, Fla.- This past July, the Jacksonville Sheriff's Office responded to a shooting on Peach Drive, which shocked the blue-collar neighborhood on the Southside.

"I was laying in bed and I heard three gun shots," one resident said. "Seven or eight minutes it was swarming with cops."

Michael Centanni had left his home and walked across the street to his neighbor Keegan Robert's home, according to reports.

"The guy came across the street and was talking about a piece of paper on his property," said Diallo Sekou, a community activist.

Sekou said Roberts was in his car with his wife sitting in the driveway when an argument ensued.

"They asked the guy to leave, he kept banging on the front window and he began to tape a note on the window," Sekou said. "Keegan got out, a scuffle ensued, shots rang out."

Centanni shot Roberts, 23, according to reports. Roberts would die from his wounds. Four months later, a reminder hangs in his driveway.

Sekou is disappointed in the State's Attorneys decision not to file charges against Centanni.

"It was murder in my eyes from my investigation," he said.

Attorney John Phillips is also upset. He represents the Roberts' family.

Phillips met with prosecutors on Monday and posted a picture of a chart used during the discussion on his Facebook page. It revealed how prosecutors weighted their chances of a conviction to reach their decision. The outcome in all of the different scenarios was not guilty.

"If you're a prosecutor and you are going to do your job ethically, you have to apply the burden of proof ," said Attorney Curtis Fallgatter.

Fallgatter, a former federal prosecutor, said the metric used by prosecutors is used in all cases.

Can you obtain a verdict beyond reasonable doubt?

"Good prosecutors don't charge based on probable cause," he said. "They charge based on whether they think, ultimately in front of a jury, they can win the case beyond a reasonable doubt."

Having worked on the other side of the legal table, he said the system works.

"They're not going to walk away from a case if they think they can win it," Fallgatter said. "The family needs to know that."

He said even if the family fails to have their day in a criminal court, this does not preclude their right to file a civil lawsuit against their neighbor.

The burden is a lot lower in civil cases.

Robert's wife was unavailable for comment. Centanni did not respond to our request for comment.