and he shot merely because he felt threatened by it's presence , witnesses also say the same thing.

If you are openly carrying a gun, you have to be cognizant of how others might perceive that. Foster walked up to Perry's car with a gun out, which, when combined with the other protestor's being angry and in the context of people having been dragged out of their cars in the past, could reasonably be perceived as threatening and intimidating.

So, I don't think Perry's defense is far-fetched. That being said, I don't think Perry is a good guy or innocent either; I personally believe he went there looking for trouble and happened to find another guy looking for trouble and they clashed.