That would be a simple problem to solve. Toy guns don't fire projectiles that travel in a straight line at 1,700 mph (the average speed of a bullet). One coul

That would be a simple problem to solve. Toy guns don't fire projectiles that travel in a straight line at 1,700 mph (the average speed of a bullet). One could easily build a system that tracks the velocity of any object traveling in a confined space, and only engage the source of an object that it determines to be a traveling bullet. Additionally, the system wouldn't have to use deadly force - it could focus on disabling the suspect with a stun gun or on destroying the actual weapon the shooter is firing.