They are called "Badia" police and are the local, Bedouin police force dealing with local matters. Generally Jordan police force doesn't interfere in Bedouin communities unless a serious crime has taken place and leaves ordinary law and order matters to the "Badia." The dagger itself is often called "Badia dagger." Materials, workmanship and general quality of the daggers is low, and I simply didn't manage to find a good Shibriya dagger during my stay in Jordan. I attached a photo of the few examples displayed in the Amman Amphiteatre Museum.
PS: Petra is definitely a must see... at least once in a lifetime!