Originally Posted by Yosemite
I got the impression from the OP that the owner just dumped the bag on the x-ray belt with her other bag in a hurry and didn't think to even tell the security people it contained a cat so I would think that the onus would have been on the owner to let them know there was a cat in the bag before it went through X-ray.
I don't know how security works anywhere else, but I fly all the time with my dog in Canada and even before I get to the front of the line, one of the security officers would be telling me to make sure I take my dog out of the carrier. They double-check everything before it goes through the x-ray machine, to ensure that everything's done right (pets out of the bags, laptops out of laptop bags, jackets off, etc.).
I think it's important for them to ensure this because some people travelling first time with their pets may not be aware of these policies, so IMO, the onus is half-half.
Additionally, before they scan my things, they always ask for my ID and boarding pass...the check-in personel is supposed to put in big blue letters PETC on the boarding passes for reasons like this (because of this, those travelling with pets *cannot* self check-in -- it's always manual check-in with a rep). Maybe policies aren't the same everywhere else. *shrugs*