Last month I had a FedEx security manager that works specifically for/with the USPS here at FedEx on a jumpseat. He said it was illegal to scan ANY of the priority mail. Why you might ask?..... he said that "package profiling" was not tolerated by the post office. FedEx can scan their stuff but none of the USPS junk is every checked.
The post office is already dumming him down. Yikes!!