Switchblades and Crime Myths

Volokh Conspiracy had a puzzle post on switchblades, which long ago were the subject of a civic moral panic, perhaps centered around the movie Blackboard Jungle.  As teen culture rose to prominence in the 1950's, the violent teen with a blade was feared, and we passed laws banning switchblades.

Amy Wilson at the Rural Blog links to a post at Metrotrends Blog on 10 crime myths. For anyone under 40 you're safer from crime now than you've ever been.  I'd question his statement on fingerprint matching being "entirely subjective" but otherwise it seems well founded.

My point: the public can panic based on false impressions.

What's the puzzle: what category of people is excluded from a switchblade ban?  Go to VC for the answer.

[Updated to change to "moral panic".