The shooting scene is in the neighborhood where both men lived.
Police say the two men had been arguing for about 15 minutes before the shooting.
The attorney for Simmons says McNair threatened Simmons' life, and those of his family.
The pair met on a roadway, and Simmons told police he says he was scared for his life. He claims McNair reached into his car, refusing to show his hands. That's when Simmons shot his neighbor.
"What we're looking at is whether or not the shooter had a reasonable belief that his life was in jeopardy and that he was justified in using deadly force," said Montgomery County District Attorney Risa Vetri Ferman.
Thursday afternoon, a very conflicting picture of McNair began to emerge. To his cousin he was a North Philadelphia real estate investor. To his neighbors he was a belligerent ex-con with a rap sheet that made repeated threats.
"The shooting victim in this case was somebody I can only characterize as the neighborhood bully, from everything we've learned so far. He was very menacing," Ferman said.
McNair's family disagrees. Speaking on their behalf, McNair's cousin Lewis Nash said "He was a very great cousin to me, his family is going to miss him."
Nash added "He had no weapons. Let me say that again, there were no weapons found."
Speaking to reporters, Nash was outraged. At first he suggested race was a factor, then amended that to say Simmons, who's African-American, is getting special treatment because he's a police officer.
Meanwhile, neighbors spoke out about McNair, including one who had a confrontation with him.
"He said I'm going to kill you, I'm going to get you, you can't hide. You never know when I'm going to get you, I'm going to get you. And he said 'I'm going to get your wife,'" said neighbor Kevin Rodzinak.
Last January, McNair had been involved in an altercation with Rodzinak. One of McNair's rottweiler's attacked Rozinak's smaller dog. Rodzinak reportedly shot the rottweiler to death. The shooting was ruled justified.
Neighbors say they've been under stress for some time. They tell Action News the community held a meeting last winter about McNair, over concerns about his behavior.
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