FBI Director Kash Patel is making bureau staff take polygraph tests to root out anyone who’s been talking trash about him, according to a report. Patel has ramped up the FBI’s use of the lie-detector tests—often deemed too unreliable to use as evidence in criminal courts—in order to keep tabs on his own people and stamp out leaks.

Some senior officials who took the test were asked whether they said anything negative about Director Kash Patel, in a highly unusual use of the tool.

Since Kash Patel assumed charge as the Director of Federal Bureau of Investigation (FBI), the agency has intensified its reliance on polygraph tests — not just to guard national secrets, but to test employee loyalty as well,