"Stand-Your-Ground" law is a variation on the older, more established "Castle Doctrine", the widely accepted legal principle that “a man’s home is his castle”.
The Castle Doctrine is the rule of law that says that a person is allowed to defend themselves within the confines of one’s own home. It applies only to outside threats made inside the home. Traditionally in American law, when threatened outside your home, the law requires you to either retreat or escape, if possible, before using lethal force. In the public realm, evasion or escape must be tried first, before killing anyone. It is common social sense.
“Stand-Your-Ground” — law designed & written by the National Rifle Association (NRA) — upends that long held principle of lethal force only as a last resort in the public sphere. "Stand-Your-Ground" laws do not require a citizen to try other means first. The NRA-modeled “Stand-Your-Ground” laws allow any citizen to shoot & kill any other citizen within the public space whenever someone feels “threatened”.
The NRA-written law in Florida passed legislative hurdles so successfully in 2005 that the American Legislative Exchange Council (ALEC) decided to spread the law. ALEC is the far-right-wing conservative lobby/think-tank — founded by The Koch Brothers — funded by corporations. ALEC is designed to write legislation & get it passed into law.
And ALEC did just that.
Most of the current wave of right-wing legislation being passed thru mostly Republican-controlled State houses is written by ALEC. Conservative legislators rarely change any of the bills that ALEC writes for them. The bills get passed as-is.
These are NOT bills being written by State legislators.
"Stand-Your-Ground" legislation is (only) one such ALEC driven law.