Louisiana - R.S. 14:95. Illegal carrying of weapons is...
  (1) The intentional concealment of any firearm, or other
   instrumentality customarily used or intended for probable
   use as a dangerous weapon, on one's person; or
  (4) The manufacture, ownership, possession, custody or use
   of any switchblade knife, spring knife or other knife or
   similar instrument having a blade which may be
   automatically unfolded or extended from a handle by the
   manipulation of a button, switch, latch or similar
   contrivance...


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