Pennsylvania's gun laws are very clear, the knife laws are fifty shades of vague, with no statewide preemption statute. Switchblades, gravity knives and double edged blade knives are illegal to carry. There is no official blade length statute. Assisted opening knives like the Kershaw Speed Safe series are sold just about everywhere and seem to be legal under the state definitions. Ballisong knives are legal, as long as the blade is not double edged. That said, everybody thinks they are illegal here. Local jurisdictions can make up just about any knife rules they see fit.

I carry a 3 inch blade assisted opening knife all the time. In 90% of the state it is no big deal, however it seems all knives are illegal to carry in Philadelphia.

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