When a passenger purchases an airline ticket, his name is checked against a no-fly database and a selectee list, both of which were created in 2001. If the no-fly list is tripped, airlines are to refuse boarding and notify the FBI. Those who trip the selectee list are put through additional security screening prior to boarding. The TSA took over its management in 2002. Details on the machinations of the databases, including the name-matching technology, is not publicly available, but there is no standardization between the airlines. Many use a phonetic-coding system to help reduce typing errors and to identify non-Western names, but generally cultural origin or name genealogy is not considered.

More problematic is that there are over 12 separate terrorist watch lists in nine federal government agencies. DHS must?and has been tasked to by the DHS inspector general?compile one single list, but efforts continue to be ad hoc. Condensing the lists to one was a mandate by Congress and President Bush following 9/11 and was to be finished no later than April 2003. In addition to multiple lists, the data on the lists is frequently outdated, inconsistent, and contradictory to other lists.