Murder or not?????

Today I was watching Book TV, yes I know I'm a nerd, and this book came up: Last Words of the Executed. My Grandma Cookie and Papa Harley brought up the points that no one cares what murderers' last words are and that murderes should get executed in the same way they killed their victims. I found the latter extremely inhuman and quite cruel. Humans do make mistakes and that's the reason of being human. To make mistakes and be forgiven, also to forgive. The idea of having other human beings who are supposebly there to help and protect and make things riht and just in America MURDERING these criminals just because they want to make them suffer is repulsing. I can't even believe my grandmother thinks that way. Totally discombobulated I found that I couldn't even form a reply to her random comment. So What do you think? Is my grandma ,and mom: because I asked her and her reply was quite similar to Grandma Cookies, right?? Or am I right in believing that her ideas are totally inappropriate and unnecassary????