That officer says most officers never have to fire their gun in the line of duty, and they are glad they didn't. That's because the decision to shoot is one that permanently changes the lives of many people.
The result of the confrontation between Walker and police was sad on many levels.
At times, Walker pointed the gun at his head and other times he cried out. However, when Walker, who friends say was despondent, pointed his gun at an officer, experts say he left that officer with no choice but to shoot.
Walker later died.
Even though many believe his intentions were "suicide by cop" that didn't make it any easier on any of the officers involved.
"This thing, you know, it goes way beyond the people that are involved in it," said retired police officer Martin McLamb.
McLamb, who is a retired Raleigh homicide detective, now trains private security guards on responding to deadly threats at his Benson shooting range. He says now Walker's family and friends will have to live with what happened as will Cpl. R.C. Swartz and his family and friends.
McLamb says unlike TV shows and movies, police officers are not trained to shoot guns out of people's hands.
"They are trained to shoot, to stop or overcome the threat," said McLamb.
That means shooting at what is referred to as "center mass," which the target the officer is mostly likely to hit quickly. McLamb says officers don't have time to consider whether someone is committing "suicide by cop" once a gun is aimed at them.
"You've got to level that gun and you've got to pull that trigger," said McLamb, "and at the most, you're going to have about two seconds."
Any delay and it could have been the officer who ended up dead.
"It's unfortunate that it ended the way it ended, but that was circumstances that was way beyond that officer's control," said McLamb.
Swartz is on administrative leave which is standard after this kind of incident.