Man Protects His Sister from Attack

What should he have done? Man shot by girlfriend’s brother during fight in southwest Las Vegas, police say

When officers arrived, Price said the brother immediately identified himself as the shooter and was detained. Inside the home, officers found a male suffering from an apparent gunshot wound. They gave the man aid until medical first responders arrived and pronounced him dead at the scene, Price said.

The brother and sister said that the boyfriend was beating the sister.

After attempting to get the woman’s boyfriend to stop hitting her, Price says the brother “produced a firearm and shot” the boyfriend.

I don't know what the laws in Nevada are, but this sure sounds like a justifiable defense of self, or other.