It found problems in each of the more than two dozen applications it reviewed, including “apparent errors or inadequately supported facts."
Those rules, or “Woods Procedures," were developed in 2001 with a goal of minimizing errors in the surveillance applications, known by the acronym FISA.
Each of the 25 other applications it reviewed contained “apparent errors or inadequately supported facts," the inspector general said.
The FBI and Justice Department say they have begun making significant changes, including additional training and other safeguards meant to ensure the accuracy of surveillance applications.
“As Director Wray has stressed, FISA is an indispensable tool to guard against national security threats, but we must ensure that these authorities are carefully exercised and that FISA applications are scrupulously accurate," Abbate wrote.