The portion of WI weapons laws that deals with knives says...
- 941.24. Possession of switchblade knife. (1)
Whoever manufactures, sells or offers to sell, transports,
purchases, possesses or goes armed with any knife having a
blade which opens by pressing a button, spring or other
device in the handle or by gravity or by a thrust or
movement is guilty of a Class A misdemeanor...
The overriding verbiage of the CCW statute is 941.23 says,
Any person except a peace officer who goes armed with a concealed and dangerous (emphasis, mine...) weapon is guilty of a Class A misdemeanor.
It provides no definition as to what a "dangerous weapon" is.
So the knife laws are rather open-ended.
It seems to me they were more worried about putting the kabosh on switchblades during the nation-wide period of "West Side Story" hype in the 50's and early 60's than anything else.
Otherwise, it leaves lots of discretion to LEO's, DA's, and the judiciary. So in day-to-day life, "dangeroups weapon" is determined by context and intent. A 16 year-old stockboy with a box-cutter waiting to take the bus home from his job at the supermarket? Cool. Pervert with a box-cutter skulking about a girls dormortory at 3 am? Not cool...
There's no length limitations, and by the wording above, "
pressing a button, spring or other device in the handle or by gravity or by a thrust or movement", "assisted openers" like the Kershaw's are legal. (WI Wal-Mart's and other places sell them at any rate...)
Unlike a firearm, a clean-cut guy, or even a relatively seedy guy, minding his own business, would probably never have a problem with most kinds of folder's, inside a pocket, clipped outside, or in a belt-pouch, save for schools or anywhere there's a security checkpoint. (i.e. airports, jails/prisons, courthouses.)
When I'm worried about being PC, but want a blade with me anyway, I just carry a Leatherman Wave or Surge. The drop-point blade is instantly accessable without unfolding the pliers inside just like many other knife-only folders. Nobody cares. Assuming some bliss-ninny sees it and actualy goes beond thinking "gadget geek", (it's never happened to me) you can unfold the pliers and all the screwdrivers first.
About the only places a multi-tool isn't welcome have checkpoints and metal detectors at the door. The other exception is grade and high schools with their zero-tolerance policy. Even then, as a non-student adult who had business in the school, (kids, voting, etc. ) I'd wager nobody would notice 99% of the time...