Congressional study questions port security efforts

WASHINGTON (CNN) - A federal program to prevent terrorists from smuggling weapons of mass destruction aboard cargo containers has holes that make it difficult to determine if security objectives are being met even after improvements, congressional investigators reported Tuesday.

Under the program, the Customs and Border Protection agency reviews the security practices of shipping companies and rewards companies who meet standards with benefits, such as reduced scrutiny of their cargo. The program has been improved in the past two years, according to a Government Accountability Office report, but CBP has had problems verifying that companies' security practices meet its standards.

"Until CBP overcomes these collective challenges, CBP will be unable to assure Congress (that participating companies) actually employ adequate security practices," the GAO report says.

The Department of Homeland Security says the likelihood of terrorists smuggling a weapon of mass destruction into the U.S. aboard a shipping container is small, but the potential consequence is enormous. A 2002 exercise by Booz Allen Hamilton concluded that a weapons detonation in a U.S. seaport would result in a shutdown of all U.S. seaports for 12 days, costing the U.S. economy an estimated $58 billion.