Dec. 19, 2014

A congressional inquiry into the F.B.I.’s scientific work on the anthrax mailings of 2001 has identified major gaps in genetic evidence that purportedly links the germs to Bruce E. Ivins, the Army microbiologist blamed for attacks that killed five people, sickened 17 others and shook the nation.

The Government Accountability Office study, requested in 2010 and made public on Friday, echoes earlier criticism from the National Academy of Sciences. In 2011, its expert panel found that the bureau’s analysis of the genetic evidence “did not definitively demonstrate” a firm link between the mailed anthrax spores and a sample taken from Dr. Ivins’s laboratory at Fort Detrick in Maryland, and more generally was “not as conclusive” as the bureau had asserted.