Handicapped Parking Permit "Checker"

I was shopping at the mall today, and while driving around looking for a parking space, I noticed the mall security people doing something odd. They had a small handheld device, about the size of two packs of cigarettes laid end-to-end. He would point it at the Handicapped Parking Permit hanging from a vehicle’s rear-view window, and then look at some sort of display on the unit. I assume it was to verify the authenticity of the permit. Does anyone know how it works or what they are checking for? Are counterfeit permits that much of a problem? I know some temporary permits issued by doctors have an expiration date, would there be an easy way to encode a date that could be read this way?

Thanks,

MC$E

I don’t know either. I have not seen this yet. I would think there are going to be scores of happy people around knowing that the scammers and the unneeded are going to get their hands slapped over this much hated abuse by the non-handicapped.