NEW YORK -- The U.S. Government Accountability Office (GAO) has called into question the effectiveness of the Transportation Worker Identification Credential (TWIC) program.

According to the Journal of Commerce, some members of Congress are having second thoughts about system after the GAOs findings were released.

The TWIC is a biometric security credential required by the Maritime Transportation Security Act of 2002. The card is issued by the Transportation Security Administration to truck drivers who have access to U.S. shipping ports.

(Canadian drivers with FAST cards do not have to undergo another security-background check, but must still obtain a TWIC card at a cost of $105).

GAO investigators were reportedly able to go onto port property with TWICs acquired fraudulently.

In one case, they entered the port with a truckload of fake explosives, the JOC reported.

Investigators concluded that the TSA lacks the internal controls to assure the eligibility of TWIC applicants to acquire the biometric card.

Rep. John Mica, R-Fla., chairman of the House Transportation and Infrastructure Committee, questioned whether the nation's ports are any safer under TWIC.

Ten years and $500 million in costs later, the U.S. still does not have a workable port security card, he said.

Sen. Frank Lautenberg compared the program to trying to solve a Rubik’s Cube: You don’t know where to start or quite where to stop."