Missouri doesn't have the Stand your ground law
True enough. Mo. calls their law Stand Your Ground law "The Castle Doctrine".
Castle Doctrine
Missouri is a castle doctrine state with a “stand-your-ground” law. The state enacted a castle law in 2007 that removed the duty to retreat for persons who are attacked within their home or vehicle. The new law justifies the use of deadly force when victims reasonably believe their lives to be in danger, and provides them immunity from civil and criminal action.
http://civilliberty.about.com/od/guncontrol/a/Missouri-Gun-Laws.htm