Criminal defendants demand to see FBI's secret hacking tool

A secret FBI hacking tool, used to compromise the Tor anonymous browser in one investigation, is facing challenges from criminal defendants, perhaps putting its future in doubt.Defendants have demanded to see details of the FBI network investigative technique (NIT), the agency's name for the relatively recent hacking tool, in a handful of criminal cases, but the agency has refused to disclose the information.A judge in a high-profile child pornography case, in which a website called Playpen was