The agent does have the ability to exempt or designate a selectee during the check-in process. There are a number of specific reasons for exemptions (FAA, airline employee, active-duty military, law-enforcement officers, etc) and each exemption is noted and copies are supposed to be made and kept on-file for a set time-period. An agent can also designate a selectee by stating that the customer does not have a valid gov't issued ID when the question is asked during the process. Overall, the system is based on a designated criteria set forth by the government that we are all aware of but as an agent cannot disclose to the customer.