Lieberman, I-Ct., said the GAO's probe included such troubling findings as a report that 73 percent of FPS contract guards lacked valid certifications and a report that one security guard allowed a baby to pass through an X-ray machine -- breaches in security he said make the country vulnerable to terrorist attack. Lieberman said the guard, who was later fired, filed a lawsuit and won after FPS could not provide sufficient proof that he had been properly trained. The GAO report found that a vast majority of security guards received no X-ray or metal detection training at all.