It is obvious that Euthanasia is important for the animal shelters, when the animals are too old, sick or aggressive to be adopted. They will be euthanized. Apparently, Euthanasia sounds really merciless. Although animals does not have the choice to choose rather be euthanized or not, human does. Because everyone has the right to choose how they want to end their life. It is kind of different for the criminals. Personal speaking, Euthanasia should be legalized for the death penalty. Even need to die, why not die in a happy way.