Should illegal immigrants, without a valid drivers license, be allowed to drive a vehicle in America?

I ran lasar radar for many years. i have stopped many speeders. some are American citizens that have no drivers license. they are taken to jail. i have stopped many illegal immigrants that only have a drivers license from their home country. they are allowed to continue, after showing other positive identification. was this really fair? this is the law in my state. how can an out of country drivers license qualify a person to drive a vehicle in America? they do not know the rules of the road or even what our road signs mean. why does one have to go to jail and the other is set free?