A non-Samurai may not carry a sword around (much less use it.) Is this a ban on carrying, or outright ban on possession and use? Example, a sword maker or polisher is almost always in possession of a useable katana and, it seems, can use it to defend himself within his private domain.
Depends somewhat on the period we’re talking about. Prior to unification in the latter half of the 16th century, there were no restrictions. Following unification, non-samurai were forbidden from possessing weapons (as part of the sword hunts) and from using violence to settle disputes. Later, during the Edo period, non-samurai were allowed to carry wakizashi for protection but were still forbidden from possessing katana (which by that time had largely become status symbols rather than weapons).
Thanks for the reply and the link.