Thank you for coming in, Chris
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I believe that, although Portuguese cuttlery has significant presence, with tracks back to the 17th century, in parallel with Spanish expansion (their Kings were ruling in Portugal at the time), the career of our neighbor's navaja was more emphasized by writers, result of its profusely use by the common Spaniard. I suspect the Portuguese locking systems were plain manners to prevent the navalha to close in their hands and not those belic ratchet systems from (some) Spanish navajas. But i am playing a bit by ear, as i do not find solid material to expand better the subject.
Concerning the law, the old illiterate saying was that a blade to be legal to carry, must not be longer than a palm of the hand ... cross wise. The written law says that a blade longer than 10 cms. is considerd a weapon, thus ilegal.
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