Before talking about this topic, I want define what is a teenager first. We usually call teenagers young people who are between 13 and 19. but when we look around, even children who are under 13 do everything like an adult. They not only know the harms they might bring to others if they commit crimes, but also, they know the laws and understand how to protect themselves from being seriously punished. Only adults thinks that they are just children. In that case, making laws that give criminal teenagers a chance to start a new life sounds unfair to the victims. As the pace of modern society goes rapidly, children receive every day a massive amount of information which allows them to grow their intrinsic value at an early age. If we still treat them as children, it's our fault. So, I think that teenagers are not supposed to receive adult punishment when they commit major crimes but, in that case, we need to redefine what is a teenager. Should it be someone under 10, or 6? We have to make sure that a real teenager doesn't have a capacity of committing major crimes rather than protecting a person who is 19 but who is as strong as you and has wrong values.