A federal report says Lawrence Berkeley National Laboratory in California allowed some subcontractors to hire employees who were using Social Security numbers assigned to dead people.
The Berkeley lab is one of the federal government's top research labs for renewable energy and energy efficiency.
The Energy Department's Inspector General Gregory Friedman said Wednesday that some outside contractors failed to ensure that employees hired to work at the lab were authorized to work in the U.S.
Inspectors reviewed 236 Form I-9s from 19 subcontractors doing infrastructure upgrades to the lab and found that 32 lacked required documentation, such as a Social Security card, driver's license or permanent resident card.
Lab spokesman Jon Weiner released a statement saying officials "concurred with the findings." The statement also said that lab officials "have taken, or are in the process of taking, the necessary steps to ensure that our subcontractors abide by the guidelines."