Is a real-life Dexter justifiable?

In relation to the recent Dexter season finale, do you think a real-life version of someone like that is okay? If you don’t know who Dexter is, he is a character on the show “Dexter” who feeds his killing urges by murdering very bad people, like other murderers, rapists, etc. I’m just wondering if you think someone like that in real life would be okay? Do you think there would be a public outcry to catch someone like that if society found out that this person existed?