The federal government’s system of tracking immigrants’ status is so broken that it gives a green light to one in eight aliens who have been ordered deported, according to an audit that found the government has gone on to approve some of those who slip through for work in sensitive areas of airports and granted them benefits such as Medicaid or food stamps

Some of those aliens who should have been kicked out had serious criminal records, including for assault and extortion, according to the audit by the Homeland Security Department’s inspector general. All told, some 800,000 immigrants are living in the United States who already have been ordered deported but have not yet left — or been removed by the government — from the country. The Homeland Security Department is supposed to maintain an up-to-date list of those deportable aliens so that other government agencies are aware of their status and know that they should be denied benefits. The system is known as the Systematic Alien Verification for Entitlements program, or SAVE. But a random sample of queries to the system found that 12% of the time, the system OKs an immigrant who should have been deported. “The failures in our sample include individuals who applied for unemployment and disability insurance, food stamps, driver’s licenses and other benefits,” the auditors said. “Several individuals had criminal records, including assault with a deadly weapon, extortion, drug convictions and other convictions such as burglary, stalking and child abuse.” Immigrants can be ordered deported for many reasons. Some are illegal immigrants who were never granted admission in the first place, while others are legal immigrants or temporary visa holders who committed crimes that should get them deported. The auditors found one case where someone earned a green card in 1983, was convicted of multiple felonies including extortion and abuse, and was ordered deported in 2003, but whom the SAVE system still green-lighted when the California Department of Health Services checked his status. Another man was convicted of homicide and manslaughter, was ordered deported but was still green-lighted by SAVE when the District of Columbia checked to see if he was eligible for student aid.