Extended punishment

Does "thou shalt not kill" refer to only manslaughter or does it include legal killings? I think it also refers to legal killings. I think "in those days men shall desire to die, and death shall flee from them" refers to future punishment actually being extending the lives of criminals, to make them stay with their act for longer (until they conscientially discover the error of their ways through long living).Message #animalsG. Eiríksson.