<font face="Verdana, Arial, Helvetica, sans-serif" size="2">Originally posted by UAL Traveler:
From the ual.com FAQ
What documentation is required for ticketed passengers to pass through security checkpoints?
It is recommended that you carry a government issued form of identification with you. Customers traveling on international flights must have a valid passport. The FAA has issued several new security measures that address access through airport security screening checkpoints.
To enter the secured area beyond the security screening checkpoint, you must hold one of the following boarding documents indicating a flight departure for the current date:
A receipt for an electronic ticket;
An itinerary generated by an airline or travel agency confirming an electronic ticket;
A boarding pass; or
A paper ticket.
If you do not have a boarding pass, ticket, e-ticket receipt or printed confirmation, an airline-issued boarding document must be obtained at the ticket counter prior to clearing security. Passengers who do not have baggage to check and already have an approved boarding document, as outlined above, may proceed through the security checkpoint directly to the departure gate.
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Thus far, ever security checkpoint has asked me for ID in the US. Less so in Asia.
It depends on the airport. Some check both, some check only one. It is UNIVERSAL that ID and BP are checked at check-in and at gate. Since this is the case, you could make the argument that anyone should be allowed through security. Either your systems work or they don't. Before 9-11, someone else could check-in and board since no one checked id at boarding. I believe that due to the long lines caused by increased security post 9-11 is why only people with BP are allowed beyond security.