The J. Edgar Hoover FBI Building in Washington, D.C. (Bonnie Jo Mount/The Washington Post)

Employers are increasingly turning to the FBI’s criminal databases to screen job applicants, sparking concerns about the accuracy of the agency’s information and the potential for racial discrimination.

Many of the FBI’s records list only arrests and not the outcomes of those cases, such as convictions. Consumer groups say that missing information often results in job applicants who are wrongfully rejected. A lawsuit filed against the Commerce Department by minorities alleges that the use of incomplete databases means that African Americans and Hispanics are denied work in disproportionate numbers.

The FBI’s background checks “might be considered the gold standard, but these records are a mess,” said Madeline Neighly, staff lawyer at the National Employment Law Project.

NELP is slated to release a report Tuesday showing that the FBI processed nearly 17 million employment background checks last year — six times more than it did a decade ago. The advocacy group estimates that as many as 600,000 of those reports contain incomplete or inaccurate information.

In a statement, the FBI said it receives its data from state records agencies, and states are responsible for keeping the information updated.

Find out how background checks are falling short.

Background checks can serve as important safety precautions, helping to ensure that sex offenders do not get hired at day-care centers, for example. The FBI emphasized that the agency is not involved in hiring decisions, but the number of industries that use its data to screen workers skyrocketed after the 2001 terrorist attacks. Because of new regulations, port workers, truck drivers and even mortgage processors must now undergo FBI background checks, turning the agency’s rap sheets into a virtual gateway to millions of jobs.

The issue has gained traction on Capitol Hill amid the tepid economic recovery and the tight job market. Rep. Robert C. “Bobby” Scott (D-Va.) is planning to introduce a bill this week that would require the FBI to track down updated information within 10 days for employment screenings. A similar measure sponsored by Rep. Keith Ellison (D-Minn.) would apply specifically to background checks for federal jobs.

“Finding a job in this economy is already hard enough,” Ellison said. “No one should lose the chance to work because of an inaccurate background check.”

Detroit resident Raquel Vanderpool lost her position as a nurse’s aide in 2009 after an FBI screening turned up outdated criminal information.

Vanderpool had pleaded guilty to a drug offense in 2003, and the judge had promised that the case would be dismissed if she served a year of probation, according to a suit she filed to regain her work license. But her file in the FBI’s database was never updated.

With the country in the depths of the recession, she was unable to find another job. She eventually lost her home to foreclosure and battled depression.

“I felt like I had lost everything and there wasn’t anyone out there that could help me, or would listen to me,” she said.

She was finally able to clear her record this spring with the help of a lawyer from Michigan’s Legal Aid clinic, four years after she lost her job.

“It’s been quite a rough road leading up to fighting this case,” Vanderpool said. “It’s caused us quite a bit of damage that it’s going to take us years to really recover from.”

The FBI’s databases are the largest repository of criminal information in the country. Records are linked to fingerprints, as well as names, reducing the chances of an incorrect match.

Employers can request an FBI background check only when authorized by state or federal laws and regulations. Many industries require potential employees to be screened by the FBI before they can receive work licenses.

But the FBI databases were not intended to be comprehensive. Instead, they function as a sort of index composed of arrests; the outcomes of those cases often are not reflected in the FBI’s records. A 2006 U.S. attorney general’s report estimated that half of the FBI’s arrest records did not include disposition information.

A spokesman for the FBI’s Criminal Justice Information Services, which handles the databases, did not provide a more current estimate. However, in a statement, the agency said that it relies on the states to provide its records and keep them current.

The design “decentralizes the criminal history responsibility by making the states, rather than the FBI, primarily responsible for record maintenance and dissemination,” it said.

At the state level, many of the records are incomplete. A report by the Justice Department in 2010, the most recent available, found that in about half the states, as many as two in five records were missing final outcomes. Twenty-seven states reported a backlog of disposition data. Transmitting the information from the courts to state records agencies could take less than a day in Delaware to 555 days in Kansas.

Updating the records of those who fall through the cracks can be confusing and cumbersome. FBI regulations say that employers and licensing agencies should give applicants time to challenge and correct their records, either by contacting the FBI or the jurisdiction that collected the data. But applicants are not always given a copy of their report or told why they were disqualified. Often, the burden is on them to prove an error was made.

The NELP report highlighted the Transportation Security Administration’s move to require FBI screenings for port workers in 2007. Since then, more than 120,000 applications were initially disqualified because of a background check, according to TSA statistics. Just over half of them filed for waivers or appeals to prove they were eligible — and 94 percent of them were successful.

Meanwhile, about a quarter of the 4 million applications to work on the 2010 Census were put on hold after the Commerce Department ran FBI background checks, according to a lawsuit filed against the agency. Applicants had 30 days to prove the FBI’s information was incorrect — but the alleged infractions were not reported to them.

Among the hundreds of thousands of rejected candidates was Precious Daniels of Detroit, who was arrested in 2009 during a peaceful protest and had her charges dropped, according to the suit. Vivian Kargbo of Boston was supposed to have her records sealed after two charges from a juvenile arrest in 1996 were dismissed. Scotty Desphy of Philadelphia thought these charges from her arrest 28 years ago were expunged after she served a year of probation, but they remained on her FBI rap sheet.

“It was a dramatic screen of basically anybody with any interaction with the criminal justice system,” said Adam Klein, a partner at law firm Outten & Golden, which is handling the case. “It included the craziest things.”

The suit alleges that the Census Bureau’s FBI screening process resulted in a disproportionate number of rejections for applications from blacks and Hispanics. These minorities are arrested in higher numbers, which civil rights activitists attribute partly to racial profiling.

Forty-one percent of the census applicants who showed up in the FBI’s criminal databases were black and 20 percent were Hispanic. If certified for class-action status, the suit would cover about 850,000 people, making it the largest discrimination suit in history.

The Commerce Department declined to comment.

The NELP report called for a more “robust” appeals process that would require employers to inform applicants why they were disqualified and give them at least 60 days to dispute any errors. It said that the FBI should provide regular reports to Congress on its background checks and any effect on minorities.

“People lose their jobs. They lose their homes. They have to go on public benefits to feed their kids,” Neighly said of the inaccurate reports. “It is so damaging.”