Inspector General Michael E. Horowitz said that between 2004 and 2009, the FBI tripled its use of bulk collection under Section 215 of the Patriot Act, which allows government agents to compel businesses to turn over records and documents, and increasingly scooped up records of Americans who had no ties to official terrorism investigations.

The FBI did finally come up with procedures to try to minimize the information it was gathering on nontargets, but it took far too long, Mr. Horowitz said in the 77-page report, which comes just as Congress is trying to decide whether to extend, rewrite or entirely nix Section 215…

“The agents we interviewed did not identify any major case developments that resulted from use of the records obtained in response to Section 215 orders,” the inspector general concluded — though he said agents did view the material they gathered as “valuable” in developing other leads or corroborating information.