Originally Posted by
jpezaris
I have only second-hand knowledge, but understand that the software for TSA scans includes randomly placed false positive images to keep the screeners from becoming complacent.
This is correct, just like the magnetometers are also programmed to randomly "quota" people. Usually it's pretty transparent from the passenger point of view but 3 or 4 years ago a screener was like 'you don't actually have a gun in your bag, do you?' before re-running my bag.
Originally Posted by
narvik
If an item looks 'suspicious' or is not easily identifiable, AFAIK, they will run it through at a different angle, upside-down, or on a different side in order to get a better/different look at the curious object. is to
There can also be an argument made that it is safer that way to a certain extent... Both for the handling of the object as well as onlookers. For example, if you see something that looks like a gun or a bomb, and are able to rerun at a different angle it without opening the package you minimize both the risk of triggering the device as well as causing mass panic if someone sees it and yells out.
I believe (from random body cam video available on the internet, that when TSA does find a confirmed gun, they are generally required to evacuate the checkpoint until local police are able to clear it... So if just rerunning the bag solves the problem a. There are very strong motivations to do that.