Even though TSA has put these so-called Advanced Imaging Technology (AIT) scanners through both laboratory and operational testing, Congress's own auditing agency says it "remains unclear" that they can actually do the primary job they are intended to do.
Steve Lord, the GAO's director of homeland security and justice issues, made this point most recently in written testimony presented last Thursday to the Senate Commerce Subcommittee on Aviation Operations, Safety and Security.
"Furthermore, as noted in our March 2010 testimony," Lord wrote, "it remains unclear whether the AIT would have been able to detect the weapon used in the December 2009 incident based on the preliminary TSA information we have received."
TSA initially intended to deploy far fewer AIT whole-body-image scanners. But it changed its mind specifically in response to Abdulmutallab's attempted Christmas underwear bombing.
"In response to the December 25, 2009, attempted attack on Northwest Flight 253, TSA revised the AIT procurement and deployment strategy, increasing the planned deployment of AITs from 878 to 1,800 units and using AITs as a primary -- instead of a secondary -- screening measure where feasible," GAO's Lord told the House Homeland Security Subcommittee on Transportation Security on March 17.
Lord told that subcommittee that "operational testing for the AIT was successfully completed late in 2009 before its deployment was fully initiated." However, Lord said, "While officials said AITs performed as well as physical pat-downs in operational tests, it remains unclear whether the AIT would have detected the weapon used in the December 2009 incident based on the preliminary information GAO has received."
Three months later, in a letter to Republican Rep. John Mica of Florida, the ranking member of the House Transportation Committee, the GAO restated its assessment that the government did not know if the scanners would detect underwear bombs.
"While officials said AITs performed as well as physical pat-downs in operational tests, it remains unclear whether the AIT would have detected the weapon used in the December 2009 incident based on the preliminary information we have received," said the letter.