TSA failed to identify 73 airport employees with links to terrorism. US law and policy prevent TSA from receiving needed information. TSA relied on applicants to report their own crimes-NBC News, June 2015 report (So much for the great 'biometrics' and 'classified' methods US claims it has on hand to screen out global jihadists)

June 2015 article
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TSA "relied on credential holders themselves to report disqualifying crimes to the airport where they worked."...

6/8/15, "TSA Fails to ID 73 Airport Employees With Links to Terrorism," nbcnews.com, by Halimah Abdullah
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"A new Department of Homeland Security Inspector General report found that the Transportation Security Administration failed to identify 73 aviation employees with active clearance badges with links to terrorism. 

The people, who were employed by major airlines, airport vendors and other employers, were not identified because TSA is not authorized to receive all terrorism-related information under current inter-agency policies, the report [with portions redacted] said.... 
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Further, the thousands of records used to vet employees contained such incomplete or inaccurate data as lacking a full first name or missing social security numbers. TSA ran into particular problems in the vetting process when potential aviation employees has not committed crimes and were legal resident or citizens.

"Without complete and accurate information, TSA risks credentialing and providing unescorted access to secure airport areas for workers with potential to harm the nation's air transportation system," the report found.

The report recommended that TSA "request additional watchlist data, require that airports improve verification of applicants' right to work, revoke credentials when the right to work expires, and improve the quality of vetting data."

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The TSA agreed with the recommendations."
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From report:
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p. 2: "TSA did not perform recurrent criminal records checks similar to its terrorism vetting due to current law and FBI policies. TSA depended on 467 commercial airports and air carriers to verify credential holders’ criminal histories through a limited review process and relied on credential holders themselves to report disqualifying crimes to the airports where they worked."... 

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