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.

According to The New York Times, the FBI is using polygraph tests to measure the loyalty of its members, specifically asking if they’ve made any negative comments about FBI Director Kash Patel. FBI Integrity Project President James Davidson,