We don't know if they are right or if they are wrong. A theory is a fact until materially proven wrong. All theories are thought as true by the scientist until proven wrong, not proven right.

When they reach a certain age and find a wife or husband they should leave their parents and be a future parent themselves so that they don't deprive themselves of great things.

Neither should be put to death unless they have done it so much that it is completely not cure able. As in it is too late to rehab them back to health, because we, the society never reported their actions fast enough or they never got caught soon enough and they have fallen too low into their evil acts to be saved.

They are not other creatures, they are humans just like the victims, and they are victims also. I saw a little girl on YouTube that was less than 6 years old and all she wanted to do was hurt people, her adopted mom and dad and brother she always just wanted to kill them and she thought that would make things happy for her, she was very troubled in the mind. The possible reason was she had been sexually abused as a baby and she could remember this traumatic experience, but it lead her into just wanting to be evil and distant from others. So, my point is that the ones doing these evil acts are probably victims also of something horrible at a young age and some never are able to get help or learn how to be the righteous kind of person society really would like.

We should believe in god because everything around us proves that he exist's including when you look up at the stars in the sky you can see that the heavens aren't randomly built or that they appeared out of pure blackness that matter and element has always existed.