QuoteI don't know what conventions you have gone to, but in the last 5 years (with the exception of 1) every "Anime" con on the west coast I have been to has a "No live steel" or "No metal" policy when it comes to prop weapons.
Anime Expo, Mikomicon, ALA, AND Yaoi con all let me in as long as the weapon was securely fastened to it's sheath (usually using Zip Ties).
QuoteIt even includes ninja stars and knives because they are metal (unless your lucky and have found the plastic ones that many Naruto cospeeps use Tongue )
California Law Prohibits the ownership of metal Ninja Stars, so if you're bringing them to a convention, that falls under Illegal items.
Swords, however, are NOT prohibited under California law, not only to own, but also to be carried in public, without restriction of function. I'm NOT saying we should be able to carry around swords that are able to be drawn, Just that we should be able to bring ones in that are unable to be drawn. I think it should be done on a case by case basis.
Especially with swords that are not really functional. Someone can be hurt a lot easier with a Bokken than they can someone trying to swing a dull Kenpachi sword around. (Though i'll give you the stabbing factor.)
Not trying to come off as mean, sorry if it seems that way :/