Texas Father: Right or Wrong?

I'm going to warn anyone reading this that this is a VERY touchy subject for some people. 

I'm going to start off with the facts. On Saturday a Texas father beat a man to death. The reason that he beat this man was because he walked in on him sexually assaulting his four year old daughter. The father beat the man around the head and neck to stop the attack. The man was pronounced dead on the scene when authorities arrived. No names have been released as of yet for the protection of the little girl, but the police have stated that the man has no prior offenses. For the sake of not repeating everything from CNN you can get the whole article that I read here. 

If you've read any of my other stuff you know that I enjoy reading the comments at the end of articles to see what other people are thinking. As one might imagine the comments are pretty mixed on this one. Some people say that this man deserves a medal. Other people said that such celebration of the loss of a life is disgusting. I found the back and forth arguments to bring up interesting points on both sides of the coin. The main theme that was continually circled back to was 'this is what I would have done _____'. 

There is a topic of discussion that I have seen on multiple articles about this that I found particularly intriguing. One person said that he should have just let the justice system do it's job. That one comment sparked a huge reaction from a lot of the other readers. It showed me that,when it comes to sex offenders, not a ton of people have faith in the justice system. Either they don't get convicted or they don't get sentenced for long enough. That set my mind in motion to say the least. Can a sex offender be rehabilitated? What makes them any less dangerous than a murderer? They both take and ruin lives for their own perverse reasons. So why do sex offenders get 'treated' and released? This thought process is why a lot of people think the father is a hero. 

This made me take a good hard look at myself and wonder what I would have done if I were in this guys shoes. The problem that I run into is that I don't exactly know what I would do to someone. I would do anything to protect my kids and  I can safely say that whatever reaction I had would not be good for the person hurting my baby. I feel like, as parents and as human beings, we have a primal instinct to protect our children. When they get hurt in any way we're ready to take on the world in order keep them safe. But what do you do when you walk in on someone hurting them? I think the rational mind goes out the window and the primal side takes over. Which is exactly why I'm not capable of giving a clear answer. I can say with confidence my husband would do what this father did. I can also say with confidence that I would stand beside him 100%. 

What would you have done?