A US federal judge threw out evidence gathered by FBI against a person accused of accessing child porn on an anonymous dark web site, Playpen. This is the first time any US judge has disallowed evidence gathered by an FBI malware.
Playpen was a large child porn site accessed through the TOR anonymous network. FBI took over the site, and instead of shutting it down, continue to run the site and deployed a tool known as “Network Investigative Technique” or NIT. This was essentially a malware that allowed the FBI to obtain the IP address of those who accessed the normally anonymous web site. This tool allowed them to gather information of users of the site within the US and from around the world.
The warrant used by the FBI for the takeover of the site, and to gather the information was issued by a magistrate judge. According to the legal process in the US, a warrant issued by a magistrate judge is only valid for the geographic area under the jurisdiction of the magistrate judge. Alex Levin, one of the defendants in the case, was living in Massachusetts, just outside the area covered by the warrant in Virginia. This particular ruling is in his favour, but the fate of others snared by the same trap is unclear.
The ruling does not state that the FBI’s operations itself was illegal, but that there was a lapse and the charges would have been sustained if the FBI had just got the same warrant from a district judge instead of a magistrate judge.