But even if that's the case, there's no way to tell if a duress pin was used, right? And if you're in a place with weak legal processes and they decide possibility=guilty, then the duress pin doesn't make things worse, right? I.e. if they wanted to do something to you, then "lack of evidence due to duress pin" is no different than just "lack of evidence" i.e. the pin at least doesn't make things worse...
Duress PIN is a feature started by security systems. Entering the dress code would seam as if the security system was disabled while in the background it would contact the security company to send in the police.