Yes, reports from South Korean intelligence (via outlets like The Telegraph, NDTV, and Fox News) confirm North Korea revised its nuclear policy law in March. It now requires an automatic retaliatory nuclear strike if Kim Jong Un is killed or the command system is threatened by hostile forces.
It's a "dead hand" deterrent: pre-set protocols in the nuclear chain trigger launches to designated targets without needing further authorization or assassin ID. Exact tech is classified.