Concerns about political correctness tainted the FBI’s investigation of Army Major Nidal Hasan in the months before he gunned down dozens of people at Fort Hood in November 2009, the chairman of a House subcommittee investigating the massacre said during a hearing Wednesday.

The failures by the FBI and Army to follow warning signs properly for nearly a year contributed to “a bunch of dead people stacked up at Fort Hood,” said Rep. John Carter, the Texas Republican who represents the area, in one of many heated exchanges with a top bureau official.