Karen Greenberg was quoted in a New York Times article about paid sources in FBI terrorism investigations.
For the F.B.I., domestic counterterrorism sometimes entails stings — finding people who might commit violent acts in the future and testing how far they’re willing to go. This task often falls to paid informants like Torres, who can spend months grooming their targets and steering the conversation toward jihad. In cases in Miami and Newburgh, N.Y., informants have offered their targets tens or hundreds of thousands of dollars to commit an act of mass violence. ‘‘Some Al Qaeda cases were so aggressive, it was approaching entrapment-light,’’ said Karen Greenberg, the director of the Center on National Security at Fordham Law School. The bureau has been more moderate with recent cases against people suspected of supporting the Islamic State, especially young ones, she added.