About 30,000 applications from immigrants seeking citizenship were processed by the government even though thousands of background files used to determine eligibility were missing, congressional investigators found.
Details of the investigation by the Government Accountability Office were released by Republican Sens. Chuck Grassley of Iowa and Susan Collins of Maine Tuesday.
According to the GAO, 14 Citizenship and Immigration Services offices were missing 110,000 so-called alien files, or A-files. Such files contain applications and other documents of some noncitizens and serve as the primary file for the immigrant and help determine eligibility.
Grassley and Collins said the citizenship and immigration offices, which are part of the Department of Homeland Security, rely on A-files to help determine eligibility for immigration benefits. The files are used by homeland security and law enforcement agencies during criminal investigations and to decide whether someone should remain in the U.S.
The GAO said the citizenship and immigration agency may not have consulted A-files when processing 30,000 naturalization applications in 2005. A-files were checked in 96 percent of the naturalization cases processed that year. The agency manages 55 million A-files.
In addition, the number of applications processed without consulting A-files could have been less because workers sometimes don't record whether they've consulted the files, the GAO said.
Spokesmen at Department of Homeland Security and Citizenship and Immigration Services could not be reached immediately Tuesday evening.
Grassley and Collins said they requested the investigation after the Homeland Security agency granted U.S. citizenship to a suspected terrorist, without checking an A-file, in 2002.
"It only takes one missing file of somebody with links to a terrorist organization to become an American citizen," Grassley said in a news release.
The missing files also cause delays for immigrants with no security issues from becoming U.S. citizens, the senators said.
The senators said the agency agreed with the GAO to require workers to record whether an A-file was used to process a naturalization application and to use an automated file tracking system.